Officials raised the death toll by eight a day after security forces cleared a blockade of a fuel plant by anti-government protesters in the city of El Alto, near La Paz.
The public defender's office and the state Institute of Forensic Investigations said the latest deaths happened in El Alto. People gathered at a Roman Catholic church to mourn the dead said they were fired on by security forces there.
Police and soldiers were escorting gasoline tankers from the Senkata fuel plant to ease food and gasoline shortages in some Bolivian cities. The plant provides fuel to more than two million people in El Alto and neighboring La Paz.
Demonstrators were attempting to blow up the plant with explosives, which could have caused a "massive tragedy," interim Defense Minister Fernando López said.
Bolivia has been in a state of turbulence since a disputed vote that, according to an international audit, was marred by irregularities. Morales resigned Nov. 10 after weeks of protests against him and pressure from security forces, but his supporters oppose the interim government that took his place.
Interim President Jeanine Áñez on Wednesday sent to the legislature a bill that would allow the scheduling of new elections, without providing a date.
"This bill can be perfected and serve as a basis for consensus," Áñez said at a news conference. She was referring to the legislators of Morales' Movement Toward Socialism party, which has a majority in congress.
"The electoral fraud caused the convulsion that the country is experiencing," she said.
Congress does not have a fixed deadline to respond to Áñez's proposal, but it is expected to deal with the matter urgently. Legislators were scheduled to meet Wednesday night.
Bolivia's constitution says elections must be called within three months of an interim president taking office, which Áñez did on Nov. 12. If the bill is approved by legislators, the date would be set by the new Supreme Electoral Tribunal, whose members will be elected within the next 15 days by lawmakers, Justice Minister Álvaro Coimbra said.
After almost a month of protests first by Morales' opponents and then by his supporters, fuel shortages are suffocating El Alto and La Paz. Control of the Senkata fuel depot has become the most recent symbol of the struggle between the interim government and the former president's followers, who are demanding that Áñez resign.
Speaking at a news conference in Mexico on Wednesday, Morales said he wanted to return to Bolivia and would help in any dialogue and efforts to restore peace if he were allowed to do so.
Morales said he was Bolivia's "president-elect," a reference to his claim to have won the Oct. 20 vote despite allegations of fraud.
He also criticized the Organization of American States, whose investigators concluded there were flaws in last month's election. In Washington, the OAS passed a resolution to help Bolivia hold elections quickly.
Áñez has said Morales, Bolivia's first indigenous president, could face prosecution for fraud if he returns to the country.
Morales upended politics in this indigenous-majority nation long ruled by light-skinned descendants of Europeans when he took office by vowing to reverse deep-rooted inequality. The economy benefited from a boom in commodity prices and he ushered through a new constitution that created a new Congress with seats reserved for Bolivia's smaller indigenous groups while also allowing self-rule for all indigenous communities.
But many people became disenchanted by his insistence on holding on to power. Much of the opposition to Morales sprang from his refusal to accept a referendum that upheld term limits that barred him from seeking a fourth term in office. He got the courts to declare the limits a violation of his human rights to seek office. Then allegations that his supporters manipulated the Oct. 20 election led to nationwide protests.