Mexican authorities are investigating the cartel-related killing of five people in the southern state of Guerrero, the regional prosecutor's office said, after a non-government organization first reported an attack in the area involving drones and explosives.

The prosecutor's office said on Saturday that it had initiated an inquiry into the attack on a group of 30 people in the town of Buenavista, in the Heliodoro Castillo municipality.

The incident, the office said, "stemmed from the confrontation between the criminal groups La Familia Michoacana and Los Tlacos, who are in a dispute for control of the area."

The human rights NGO Minerva Bello had first reported on Friday an attack in the area using drones and "explosive devices" the previous afternoon.

Later, agents of the Guerrero prosecutor's office were able to "establish the existence of charred skeletal remains corresponding to five people in a burned-out car," the office said.

However, the bodies were taken away by the residents of a neighboring community and the officials only found the vehicle.

The director of Minerva Bello, priest Filiberto Velazquez, said on Saturday that the vehicle contained "an indeterminate number of charred bodies," but at least five skulls.

"Six survivors were reported, and the rest of the people's whereabouts are unknown," he said.

The prosecutor's office said it had not received any reports of missing people in the area.

Guerrero is one of the poorest states in Mexico, and is used by drug cartels to grow marijuana and poppy.