The protesters in Yangon were chased as they tried to gather at their usual meeting spot at the Hledan Center intersection. Demonstrators scattered and sought in vain to rinse the irritating gas from their eyes, but later regrouped.

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The coup reversed years of slow progress toward democracy in Myanmar after five decades of military rule. It came Feb. 1, the same day a newly elected Parliament was supposed to take office. Ousted leader Aung San Suu Kyi’s party would have led that government, but instead she was detained along with President Win Myint and other senior officials.

The army has leveled several charges against Suu Kyi — an apparent effort by the military to provide a legal veneer for her detention and potentially to bar her from running in the election the junta has promised to hold in one year. On Monday, Suu Kyi made a court appearance via videoconference and was charged with two more offenses, her lawyer Khin Maung Zaw told reporters.

Accused of inciting unrest, she was charged under a law that dates from British colonial days and has long been criticized as a vaguely defined catch-all statute that inhibits freedom of expression. That charge carries a maximum sentence of two years in prison. The other charge from Monday carries a one-year sentence.

Following her detention on the day of the coup, the 75-year-old Suu Kyi was initially held at her residence in the capital of Naypyitaw, but members of her National League for Democracy party now say they don’t know where she is.

Since the takeover, a movement of protests in cities across the country has been growing — and the junta’s response has become increasingly violent.

The U.N. said it had “credible information” that at least 18 people were killed and 30 were wounded across Myanmar on Sunday. Counts from other sources, such the Democratic Voice of Burma, an independent television and online news outlet, put the death toll in the 20s.

Any of the reports would make it the highest single-day death toll since the military takeover. The junta has also made mass arrests, and the independent Assistance Association for Political Prisoners reported that as many as 1,000 people were detained Sunday. Several journalists have been among those detained, including one for The Associated Press.

At least five people are believed to have been killed Sunday in Yangon when police shot at protesters, who have remained nonviolent despite provocation from the security forces and pro-military counter-demonstrators.

People erected makeshift sidewalk shrines Monday at the spots where several of the victims were shot and also paid their respects by standing outside the hospitals where the bodies were being released to families.

In Dawei, a small city in southeastern Myanmar where five people were reported killed Sunday, the number of protesters on the streets Monday was lower than usual, but they paraded to the applause of bystanders.

Confirming the deaths of protesters has been difficult in areas outside Yangon, Mandalay and Naypyitaw. But in many cases, there was evidence posted online such as videos of shootings, photos of bullet casings collected afterwards and gruesome pictures of bodies.

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In a statement published Monday in the state-run Global New Light of Myanmar newspaper, Myanmar’s Foreign Ministry declared that the junta “is exercising utmost restraint to avoid the use of force in managing the violent protests systematically, in accordance with domestic and international laws in order to keep minimum casualties.”

But U.N. Secretary-General Antonio Guterres called the use of lethal force against peaceful protesters and arbitrary arrests “unacceptable,” said U.N. spokesperson Stephane Dujarric.

“Words of condemnation are necessary and welcome but insufficient. The world must act. We must all act,” the U.N.’s independent expert on human rights in Myanmar, Tom Andrews, said in a separate statement.

He proposed that countries could institute a global embargo on the sale of arms to Myanmar and “tough, targeted and coordinated sanctions” against those responsible for the coup, the crackdown and other rights abuses.

Social media posts from Myanmar have increasingly urged the international community to invoke the doctrine of the “responsibility to protect” to intervene directly to restrain the junta.

Any kind of coordinated action at the United Nations, however, would be difficult since two permanent members of the U.N. Security Council, China and Russia, would almost certainly veto it.

Instead, some countries have imposed or are considering imposing their own sanctions. In Washington, White House National Security Adviser Jake Sullivan issued a statement saying the U.S. is “alarmed” by the violence and stands in solidarity with Myanmar’s people.

Washington is among those that have levied sanctions, and Sullivan said it would “impose further costs on those responsible,” promising details “in the coming days.”

Members of Suu Kyi’s party have also created a committee that they are asking other countries to recognize as a provisional government and the true representatives of Myanmar’s people.

The committee recently appointed a doctor and philanthropist from the ethnic Chin minority to be a special envoy to the United Nations.

In an interview Sunday night with the AP, the envoy, Sasa, who uses one name, said he would discuss with U.N. human rights expert Andrews pursuing legal actions against the generals through international courts.

“We are looking at international criminal courts and other U.N. mechanisms. It will be a little bit difficult to do it though the United Nations Security Council but we are looking at great length what can be done” to bring these generals to account, he said, speaking from a secret location due to fears for his safety.

Many expect Myanmar’s military to be intractable, but Sasa said he believes the junta is already beginning to see the difficulty of running a functioning government.

“I hope that they will come to the negotiating table, so we can talk together,” said Sasa.

Among the arrests made Sunday, the independent Assistance Association for Political Prisoners was able to identify about 270 people, bringing to 1,132 the total number of people the group has confirmed has been arrested, charged or sentenced since the coup.

Thein Zaw, an AP journalist, was taken into police custody on Saturday morning while providing news coverage of the protests. He remains in police custody.

Also read: Defying lethal shootings, Myanmar protesters back on streets

The AP called for his immediate release.

“Independent journalists must be allowed to freely and safely report the news without fear of retribution. AP decries in the strongest terms the arbitrary detention of Thein Zaw,” said Ian Phillips, the AP’s vice president for international news.

According to information collected by the Assistance Association for Political Prisoners and local media reports, at least seven other journalists were detained over the weekend — all of whom work for local media. At least another 13 have been detained since the coup.