Mexican government says it is seeking details after incident raises questions about US activities on its territory.

The Mexican government has said two federal agents from the United States killed in a car crash in connection with an anti-narcotics raid – widely reported to be CIA officers – were not authorised to operate on Mexican territory.

Mexico’s security cabinet said in a statement on Saturday that one of the US citizens had entered the country as a visitor and the other on a diplomatic passport.

US authorities have not confirmed a slate of reports that the individuals were agents with the CIA, Washington’s top international intelligence agency, in Mexico as part of a wider operation against drug trafficking.

“Neither had formal accreditation to participate in operational activities within national territory,” the statement said, stressing the need for “absolute respect” for Mexican sovereignty in the realm of international cooperation.

Mexican President Claudia Sheinbaum, who has had to balance US demands for more aggressive steps against drug trafficking with a firm insistence on national sovereignty, said earlier this week that her government would probe whether the country’s national security law had been violated.

Under the law, foreign agents must receive federal authorisation to operate in the country and cannot work directly with local officials without approval.

“Evidently, the military didn’t know there were people participating who weren’t Mexican citizens … that there were foreigners participating in the operation,” Sheinbaum told reporters earlier this week.

“This is something that Mexicans shouldn’t take lightly.”

Questions have swirled about the death of the two US agents, in what authorities have said was a car crash in the northern state of Chihuahua, last Sunday, in connection with a drug raid.

Following the deaths, US Ambassador Ronald Johnson described the two individuals as “embassy personnel”. The attorney general of Chihuahua, meanwhile, described the pair as “instructor officers” from the embassy carrying out regular training work.

In a statement, Johnson said the incident “strengthens our resolve to continue their mission and advance our shared commitment to security and justice, to protect our people”.

Two Mexican officials were also killed in the crash, which has raised questions about the extent of US participation in activities on Mexican soil and whether the country’s government has full knowledge of such operations.

The Trump administration has pledged to take a militaristic approach to Latin America to stifle drug trafficking. It has sought to reframe criminal organisations as “narco-terrorists” seeking to destabilise the US, designating several as “foreign terrorist organisations”.

Criminal drug trafficking has historically been outside of the purview of the CIA, which has focused on intelligence gathering related to national security.

Under Trump, the US has unilaterally launched strikes on alleged drug smuggling boats in the Caribbean and abducted Venezuelan leader Nicolas Maduro, campaigns that have been condemned as blatant violations of international rights.

In March, the US military also launched a joint attack with the government of Ecuador against a cartel in the country.

Sheinbaum has ruled out any US military presence in Mexico.

On Saturday, Mexico’s security cabinet said it welcomes coordination with the US in the form of intelligence sharing, institutional coordination, and technical collaboration.

It added that cooperation must proceed from a place of mutual trust.