A group of gunmen have killed 11 people in a bar in Brazil, according to media reports, with state officials confirming only at “a massacre” had occurred.

The G1 news website reported police reported that seven gunmen were involved in the attack in Belém city in the northern state of Pará, which also wounded one person, who is now in police protection.

The news outlet said the attackers arrived at the bar in three cars and one motorcycle before killing six women and five men on Sunday afternoon.

Almost all the victims had been shot in the head, G1 reported the secretary of public security in Pará, Ualame Machado, as saying.

“Of course we have some lines of investigation, which are confidential, but all of them will be analysed very carefully, very strictly,” Machado told a news conference on Sunday. As of Sunday afternoon, a motive remained unclear and no one had been arrested.

A Pará state spokeswoman, Natalia Mello, said only: “A massacre is confirmed.” State communications officials stopped answering phone calls. Military and civil police in Pará state also did not answer phone calls or respond to emails.

In late March, the federal government sent National Guard troops to Belém to reinforce security in the city for 90 days.

Brazil hit a record high of 64,000 homicides in 2017, 70% of which were due to firearms, according to official statistics.

Much of Brazil’s violence is gang related. In January, gangs attacked across Fortaleza, bringing that city to a standstill as commerce, buses and taxis shut down. Rio de Janeiro experiences daily shootouts between rival gangs, and also with police, that often kill bystanders.

One of new President Jair Bolsonaro’s main campaign promises was that he would loosen Brazil’s strict gun laws, arguing that because criminals were well-armed with illegally obtained guns, “upstanding citizens” should have the right to defend themselves. Bolsonaro has made good on that campaign promise with two presidential decrees that make buying guns easier, though federal prosecutors are seeking to get the courts to block that move.