The US government approved a sale of sniper rifles to a deadly police unit in Brazil last year, overriding concerns from the US ambassador and other diplomats that the arms could be used in extrajudicial killings, according to three current and former US officials and documents seen by Reuters.

The Rio de Janeiro police unit that purchased the guns, known as BOPE, played a central role in a raid last week that left 121 people dead, including four police officers. That action drew condemnation from human rights advocates and United Nations experts, who have alleged that some of the killings may have been unlawful.

BOPE purchased 20 sniper rifles produced by Georgia-based Daniel Defense LLC in an unannounced deal in May 2023, during the administration of former US President Joe Biden, according to internal Rio police documents seen by Reuters. The weapons were not received until 2024, amid debate within the State Department about the sale’s appropriateness, according to internal Rio police and US State Department documents.

Under US law, gun exports typically need to be approved by the government. While the Commerce Department often issues the final license, the State Department plays a key role in the process.

Elizabeth Bagley, then the US ambassador to Brazil, objected to the deal, as did some diplomats working on human rights and law enforcement issues, according to a January 2024 State Department memo seen by Reuters. That memo describes BOPE as “among the most notorious police units in Brazil in regard to killings of civilians.”

Rio police – of which BOPE is the most notorious unit – were responsible for 703 killings last year, according to official data consolidated by the Brazilian Public Safety Forum.

Reuters could not establish whether the U.S. made sniper rifles were used by BOPE in last week’s raid.

BOPE also purchased accompanying suppressors for the rifles, which were produced by Wisconsin-based Griffin Armament, but the suppressor shipment was initially blocked by the US government, according to the documents and sources. Reuters could not determine if the suppressors were ultimately sent at a later date.

In a statement, the State Department said none of the equipment would have been denied or delayed under the current administration. In April, US President Donald Trump rescinded 2023 guidance issued by Biden which put stricter human rights-related restrictions on gun exports.

“The previous administration’s disastrous foreign policies aided and abetted our hemisphere’s most violent gangs,” a State Department spokesperson told Reuters. “Last year, Biden’s State Department denied critical defensive equipment to trusted security partners in Brazil while asking them to protect President Biden during his 2024 trip to Rio. In the interest of a safer hemisphere, we remain committed to ensuring that our partners have what they need to fight vicious criminals.”