MEXICO CITY (AP) — In a strange and aggressive attack by Mexican federal police on a U.S. Embassy vehicle that was pumped with 152 bullets, one major question remains: Why?

Mexican investigators are looking for the answer from five police commanders who are accused of ordering 14 officers to lie about what happened on Aug. 24 south of Mexico City, where two CIA officers and a Mexican Navy captain came under heavy fire while travelling in an armored SUV clearly marked by diplomatic plates.