The Central Intelligence Agency is providing the bulk of the intelligence used to carry out the controversial lethal air strikes by the Trump administration against small, fast-going boats in the Caribbean Sea suspected of carrying drugs from Venezuela, according to three sources familiar with the operations, the Guardian reported. 

Experts say the agency’s central role means much of the evidence used to select which alleged smugglers to kill on the open sea will almost certainly remain secret.

The agency’s central role in the boat strikes has not previously been disclosed. Donald Trump confirmed last Wednesday that he had authorized covert CIA action in Venezuela, but not what the agency would be doing.

The sources say the CIA is providing real-time intelligence collected by satellites and signal intercepts to detect which boats it believes are loaded with drugs, tracking their routes and making the recommendations about which vessels should be hit by missiles.

Since early September, nearly 30 people have been killed in the strikes on vessels in the Caribbean that the Trump administration claims are aimed at dismantling drug trafficking networks. On Monday, Colombia recalled its ambassador to the US amid a furious war of words between Colombian President Gustavo Petro, and Trump over deadly US strikes on boats in the Caribbean.