A Mexican official says federal prosecutors have dropped organized crime charges against a retired army general accused of aiding a drug cartel after determining that the witness testimony was not enough to sustain their case.

The official says retired Gen. Tomas Angeles Dauahare will be released from a maximum security prison in Mexico state, where he has been held since his arrest last year.

The official spoke on condition of anonymity because he is not allowed to discuss the case.

He said Wednesday that Attorney General Jesus Murillo Karam studied the case begun during former President Felipe Calderon's administration and concluded that "witness testimony didn't prove guilt."

Angeles Dauahare was charged with protecting members of the Beltran Leyva cartel.

He was Assistant Defense Secretary from 2006 to 2008.