These men were migrants from elsewhere in Africa with next to nothing who sought a living in the thriving underground economy of Gauteng province, a name that roughly translates to "land of gold." Instead of fortune, many found death, their bodies unnamed and unclaimed — more than 4,300 in Gauteng between 2014 and 2017 alone.

Some of those lives ended here at the Olifantsvlei cemetery, in silence, among tufts of grass growing over tiny placards that read: Pauper Block. There are coffins so tiny that they could only belong to children.

As people worldwide flee war, hunger and a lack of jobs, global migration has soared to record highs, with more than 258 million international migrants in 2017. That is an increase of 49 percent from the turn of the century, according to the United Nations.

Far less visible, however, has been the toll of this mass migration: The tens of thousands of people who die or simply disappear during their journeys, never to be seen again. A growing number of migrants have drowned, died in deserts or fallen prey to traffickers, leaving their families to wonder what on earth happened to them. At the same time, anonymous bodies are filling cemeteries around the world, like the one in Gauteng.

In most cases, nobody is keeping track: Barely counted in life, these people don't register in death, as if they never lived at all.

An Associated Press tally has documented at least 56,800 migrants dead or missing worldwide since 2014 — almost double the number found in the world's only official attempt to try to count them, by the U.N.'s International Organization for Migration . The IOM toll as of Oct. 1 was more than 28,500. The AP came up with almost 28,300 additional dead or missing migrants by compiling information from other international groups, requesting forensic records, missing persons reports and death records, and sifting through data from thousands of interviews with migrants.

The AP's tally is still low. Bodies of migrants lie undiscovered in desert sands or at the bottom of the sea. And families don't always report loved ones as missing because they are illegal, or because they left home without saying exactly where they were headed.

The official U.N. toll focuses mostly on Europe, but even there cases fall through the cracks. The political tide is turning against migrants in Europe just as in the United States, where the government is cracking down heavily on caravans of Central Americans trying to get in. One result is that money is drying up for projects to track migration and its costs.

For example, when more than 800 people died in an April 2015 shipwreck off the coast of Italy, Europe's deadliest migrant sea disaster, Italian investigators pledged to identify them and find their families. More than three years later, under a new populist government, funding for this work is being cut off.

Beyond Europe, information is even more scarce. Little is known about the toll in South America, where the Venezuelan migration is among the world's biggest today, and in Asia, the top region for numbers of migrants.

The result is that governments vastly underestimate the toll of migration, a major political and social issue in most of the world today.

"No matter where you stand on the whole migration management debate....these are still human beings on the move," said Bram Frouws, the head of the Mixed Migration Centre , based in Geneva, which has done surveys of more than 20,000 migrants in its 4Mi project since 2014. "Whether it's refugees or people moving for jobs, they are human beings."

They leave behind families caught between hope and mourning, like that of Safi al-Bahri. Her son, Majdi Barhoumi, left their hometown of Ras Jebel, Tunisia, on May 7, 2011, headed for Europe in a small boat with a dozen other migrants. The boat sank and Barhoumi hasn't been heard from since. In a sign of faith that he is still alive, his parents built an animal pen with a brood of hens, a few cows and a dog to stand watch until he returns.

"I just wait for him. I always imagine him behind me, at home, in the market, everywhere," said al-Bahari. "When I hear a voice at night, I think he's come back. When I hear the sound of a motorcycle, I think my son is back."

EUROPE: BOATS THAT NEVER ARRIVE

Of the world's migration crises, Europe's has been the most cruelly visible. Images of the lifeless body of a Kurdish toddler on a beach, frozen tent camps in Eastern Europe, and a nearly numbing succession of deadly shipwrecks have been transmitted around the world, adding to the furor over migration.

In the Mediterranean, scores of tankers, cargo boats, cruise ships and military vessels tower over tiny, crowded rafts powered by an outboard motor for a one-way trip. Even larger boats carrying hundreds of migrants may go down when soft breezes turn into battering winds and thrashing waves further from shore.

Two shipwrecks and the deaths of at least 368 people off the coast of Italy in October 2013 prompted the IOM's research into migrant deaths. The organization has focused on deaths in the Mediterranean, although its researchers plead for more data from elsewhere in the world. This year alone, the IOM has found more than 1,700 deaths in the waters that divide Africa and Europe.

Like the lost Tunisians of Ras Jebel, most of them set off to look for work. Barhoumi, his friends, cousins and other would-be migrants camped in the seaside brush the night before their departure, listening to the crash of the waves that ultimately would sink their raft.

Khalid Arfaoui had planned to be among them. When the group knocked at his door, it wasn't fear that held him back, but a lack of cash. Everyone needed to chip in to pay for the boat, gas and supplies, and he was short about $100. So he sat inside and watched as they left for the beachside campsite where even today locals spend the night before embarking to Europe.

Propelled by a feeble outboard motor and overburdened with its passengers, the rubber raft flipped, possibly after grazing rocks below the surface on an uninhabited island just offshore. Two bodies were retrieved. The lone survivor was found clinging to debris eight hours later.

The Tunisian government has never tallied its missing, and the group never made it close enough to Europe to catch the attention of authorities there. So these migrants never have been counted among the dead and missing.

"If I had gone with them, I'd be lost like the others," Arfaoui said recently, standing on the rocky shoreline with a group of friends, all of whom vaguely planned to leave for Europe. "If I get the chance, I'll do it. Even if I fear the sea and I know I might die, I'll do it."

With him that day was 30-year-old Mounir Aguida, who had already made the trip once, drifting for 19 hours after the boat engine cut out. In late August this year, he crammed into another raft with seven friends, feeling the waves slam the flimsy bow. At the last minute he and another young man jumped out.

"It didn't feel right," Aguida said.

There has been no word from the other six — yet another group of Ras Jebel's youth lost to the sea. With no shipwreck reported, no survivors to rescue and no bodies to identify, the six young men are not counted in any toll.

In addition to watching its own youth flee, Tunisia and to a lesser degree neighboring Algeria are transit points for other Africans north bound for Europe. Tunisia has its own cemetery for unidentified migrants, as do Greece, Italy and Turkey. The one at Tunisia's southern coast is tended by an unemployed sailor named Chamseddin Marzouk.

Of around 400 bodies interred in the coastal graveyard since it opened in 2005, only one has ever been identified. As for the others who lie beneath piles of dirt, Marzouk couldn't imagine how their families would ever learn their fate.

"Their families may think that the person is still alive, or that he'll return one day to visit," Marzouk said. "They don't know that those they await are buried here, in Zarzis, Tunisia."

AFRICA: VANISHING WITHOUT A TRACE

Despite talk of the 'waves' of African migrants trying to cross the Mediterranean, as many migrate within Africa — 16 million — as leave for Europe. In all, since 2014, at least 18,400 African migrants have died traveling within Africa, according to the figures compiled from AP and IOM records. That includes more than 4,300 unidentified bodies in a single South African province, and 8,700 whose traveling companions reported their disappearance en route out of the Horn of Africa in interviews with 4Mi.

When people vanish while migrating in Africa, it is often without a trace. The IOM says the Sahara Desert may well have killed more migrants than the Mediterranean. But no one will ever know for sure in a region where borders are little more than lines drawn on maps and no government is searching an expanse as large as the continental United States. The harsh sun and swirling desert sands quickly decompose and bury bodies of migrants, so that even when they turn up, they are usually impossible to identify.

With a prosperous economy and stable government, South Africa draws more migrants than any other country in Africa. The government is a meticulous collector of fingerprints — nearly every legal resident and citizen has a file somewhere — so bodies without any records are assumed to have been living and working in the country illegally. The corpses are fingerprinted when possible, but there is no regular DNA collection.

South Africa also has one of the world's highest rates of violent crime and police are more focused on solving domestic cases than identifying migrants.

"There's logic to that, as sad as it is....You want to find the killer if you're a policeman, because the killer could kill more people," said Jeanine Vellema, the chief specialist of the province's eight mortuaries. Migrant identification, meanwhile, is largely an issue for foreign families — and poor ones at that.

Vellema has tried to patch into the police missing persons system, to build a system of electronic mortuary records and to establish a protocol where a DNA sample is taken from every set of remains that arrive at the morgue. She sighs: "Resources." It's a word that comes up 10 times in a half-hour conversation.

So the bodies end up at Olifantsvlei or a cemetery like it, in unnamed graves. On a recent visit by AP, a series of open rectangles awaited the bodies of the unidentified and unclaimed. They did not wait long: a pickup truck drove up, piled with about 10 coffins, five per grave. There were at least 180 grave markers for the anonymous dead, with multiple bodies in each grave.

The International Committee of the Red Cross, which is working with Vellema, has started a pilot project with one Gauteng morgue to take detailed photos, fingerprints, dental information and DNA samples of unidentified bodies. That information goes to a database where, in theory, the bodies can be traced.

"Every person has a right to their dignity. And to their identity," said Stephen Fonseca, the ICRC regional forensic manager.