A member of the gang that killed a mayor in southern Mexico has revealed the site of clandestine graves holding the remains of four other people.

An official of the prosecutors' office in the southern state of Morelos said Tuesday that investigators have found four bodies in two pits in a rural area.

The official spoke on condition of anonymity because he or she was not authorized to be quoted by name.

The suspect was not named because he is a minor. He was arrested with two other people last week in the killing of the mayor of city of Temixco, south of the Morelos state capital of Cuernavaca.

He told police he belongs to the Rojos drug gang that apparently killed and buried the four people, who remain unidentified.