SAO PAULO, Jan. 29 (Xinhua) -- A 13-year-old boy died Thursday after being attacked by a shark while swimming at a beach in Olinda, in Brazil's northeastern state of Pernambuco, medical officials said.

The attack occurred at the beach Praia Del Chifre, where the victim was swimming with friends despite warning signs of frequent shark activity.

Witnesses said the boy was attacked from behind, causing severe injuries. He was taken to a hospital in Olinda and died from blood loss.

According to the State Committee for Monitoring Shark Incidents, Pernambuco has registered 82 shark attacks since 1992, including 27 fatal cases.

Authorities said beaches in Recife and Olinda have warning signs discouraging swimming due to the high risk of shark encounters. The areas are popular tourist destinations, especially during the carnival season. ■