Mexico City - Francisco Rafael Arellano Felix, one of Mexico's best-known drug bosses, was shot dead in the middle of a family celebration, the newspaper Reforma reported on Saturday.
Arellano Felix was at the party in a hotel in the Pacific coast city of Cabo San Lucas when gunmen broke in and shot him in the head and chest, reported the newspaper. A shootout followed, leading to a large police response.
It was unclear if the attackers escaped.
Arellano Felix and his brothers were the core of one of Mexico's most infamous drug cartels over the last two decades, with their headquarters in Tijuana. However, most of his brothers have either been arrested or killed in recent years.
Arellano Felix was sentenced to six years in a US jail for selling cocaine to an undercover investigator. He was released early in 2008, for good behaviour, and sent back to Mexico.