JOHANNESBURG - The death toll of Thursday's shootout between the police and miners in northern South Africa has climbed to 36, a union chief said on Friday morning.

"Our shop-stewards on the ground report that 36 people were killed," the general secretary of the National Union of Mineworkers (NUM) Frans Baleni said.

Police ministry spokesperson Zweli Mnisi also confirmed Friday that more than 30 people were dead in the shootout at the mine, adding that the number of deaths could rise.

Baleni said the trade union was "extremely saddened by this loss of life, it could been avoided."

The general secretary criticized both the police and the miners for the violence, saying that "police should not be peace brokers, " while "workers have a constitutional right to protest, but have no right to be violent when you protest."

The shooting, seen as one of the deadliest conflict between police and workers since the apartheid ended in South Africa in 1994, erupted at 4:00 p.m. local time (1400 GMT) on Thursday as police attempted to disperse armed striking miners at Lonmin's Marikana mine in the northern province of the North West.

Several thousands of miners had gathered on a hill since Monday, demanding an improvement of working condition by raising their monthly salary from some 4,000 rands (about 480 U.S.dollars) to 12,500 rands.

Lonmin is the world's third biggest platinum producer headquartered in Johannesburg with approximately 28,000 employees.

Last Friday, about 3,000 drilling miners at the mine started protests, demanding a 12 percent wage increase. However, the protests turned into violence in the following days.

Up to Wednesday, the violence at the Marikana mine had claimed 10 lives, including two police officers, two security guards, three protestors and three other men.