A helicopter carrying firefighters from a forest fire crashed in southern Chile on Sunday, killing all 13 people on board, authorities said.

The helicopter hit a hillside near Chanco, some 165 miles south of Santiago, said Maule province Gov. Maria del Carmen Perez.

Twelve firefighters and a pilot were killed, said Angelica Saez, who runs the county where the crash occurred. The government previously said 14 people had died, including a co-pilot.

The helicopter had just retrieved the firefighters from a day's work battling a blaze, which was still being controlled at the time of the crash.

The firefighters were all young men between the ages of 18 and 25 who worked for Celulosa Arauco y Constitucion, a Chilean timber and pulp company known as CELCO, said Dante Bravo, head of the National Forest Service.

The fire was consuming the property of another timber company, Compania Astilladora de Concepcion, or COMACO, but CELCO had mobilized the men to keep the flames from spreading, Bravo said.

Rescue crews at the crash site reported no survivors, said Daniel Vergara, government secretary in the Maule province. An Air Force prosecutor was on his way to authorize the removal of bodies and to start investigating the cause of the crash, he said.

The helicopter belonged to Flight Service, a Maule-based company, provincial officials said.