SAO PAULO, Brazil (AP) _ A pit bull mauled to death a 1-year-old boy in the southern state of Santa Catarina, in the second fatal dog attack in Brazil in two days, authorities said Sunday.

The boy was killed in his backyard Friday afternoon after a neighbor's dog escaped from its cage in the suburbs of Florianopolis, some 700 kilometers (437 miles) south of Sao Paulo, firefighter Edson Walmor said.

The boy suffered severe wounds to his head, face and throat and was already dead when paramedics reached the scene, Walmor said.

Witnesses said the dog's owner was the first to call for help, but apparently left the scene before authorities arrived, said Walmor, adding that authorities were searching for the man.

On Thursday, an 88-year-old woman was killed by two pit bulls in Sao Paulo, and last Monday a 10-year-old boy was seriously injured in the city's east side after being attacked by a neighbor's dog while trying to recover a kite.

On Sunday, Sao Paulo state police began enforcing a law banning dog-owners from walking their dogs unleashed. Pit bulls and Rottweilers are required to wear muzzles when in public.