A drug gang in Mexico has shot and killed 20 people, including the mayor and his father, the AP reports.

In footage, men who identified themselves as the Tequileros gang claimed responsibility for the mass shooting.

The Guerrero State Security Council said the gunmen stormed a town hall in the town of San Miguel-Totolapan and opened fire on participants in a meeting between the mayor and other officials. Among the dead were Mayor Conrado Mendoza and his father Juan Mendoza Acosta, the town's former mayor.  The walls of the town hall were riddled with bullets.