BOGOTA, Colombia (AP) _ The vice president of Colombia's senate died Sunday of wounds suffered when he was gunned down in Medellin two days earlier by a hit team citing his role in writing a new drug trafficking law.

Dario Londono Cardona, 45, died of brain injuries, the Medellin Clinic said. He never regained consciousness after being shot in the head and arm at the University of Medellin, where he taught.

A previously unknown group called Death to Protectors of the Cali Cartel claimed responsibility for the attack minutes after the shooting, in a phone call to a radio station. The station gave the claim credibility because the caller knew details of the attack before they were reported.

The group said it attacked Londono because he helped write a new penal code which offers leniency to drug traffickers who surrender and tell authorities about their operations. The group, which said it backs fugitive Medellin cocaine cartel boss Pablo Escobar, said the law favors leaders of the rival Cali cartel.

The two drug trafficking organizations have been fighting a behind-the- scenes war. Cali cartel members are believed to be among members of a clandestine group called People Persecuted by Pablo Escobar, which has been murdering his followers.

Leftist guerrillas also claimed responsibility for the attack on Londono, but the claim has been given litle credence.

The government has offered the equivalent of $625,000 as a reward for information leading to the capture of the killers.