Juan Manuel Pacheco Salgado, a police inspector general, was detained Monday and sent to jail in the western state of Jalisco, the source told AFP.

Last Friday, the attorney general's office charged 14 police officers with attempted murder over the August 24 attack on a US embassy car that wounded the two Americans, reportedly CIA agents.

The two Americans and a Mexican navy captain were traveling to a military training facility south of Mexico City when their armored sport-utility vehicle was riddled with 152 bullets, prosecutors say.

Prosecutors say the officers were wearing civilian clothes and driving private cars when they shot at the SUV, which had US diplomatic plates, but then changed into uniform and brought patrol cars before investigators arrived.

Mexican media say Pacheco is suspected of having ordered the wardrobe and vehicle changes.

Prosecutors did not indicate a motive for the shooting but the source said all lines of investigation remain open, including the possibility the officers worked with organized crime, or that the attack was the result of a mix-up.