Jayapura – Enraged Indonesian police fired live bullets to root out about 1,000 protesters from a university in Papua after the students beat several officers to death, eyewitnesses said.

Three policemen and an airforce officer were killed in Thursday's melee in the restive province of Papua, where the mine run by US firm Freeport McMoRan has become a symbol of local grievances against Jakarta and Washington "The students were insulting Indonesia, yelling 'Indondesia is a robber, Indonesia protects Freeport,'" Benny Giay, a local Christian minister who tried to mediate in the dispute, told AFP.

The students had gathered outside the university in the provincial capital of Jayapura, blocking a main road and demanding the closure of the mine, which is a top source of revenue for the Indonesian government. Troops and riot squads came in after police failed to convince the students to open up the road, said Yanke Baru, a volunteer for the human rights group Elsham-Papua who was on the scene.

He said three cordons of police then surrounded the protesters – regular police, female officers, and finally the riot squads.

"Then the mass started throwing stones while police were negotiating with a student leader. The police grabbed the student leader and when other students saw police treat him so brutally, they threw many stones," Baru said.

"And that's when police started beating some students." Many in Papua complain that they do not see enough benefits from the mine and with tensions already high, the beatings apparently infuriated the crowd.

Two policemen fell in the fracas as officers chased the protesters into the university campus, Baru said. "They were beaten to death." The others were beaten later, he said.

Baru said that the shooting began shortly afterwards. "Because the students threw stones, they shot back," he said. "They used live bullets. I took 12 students injured to the (Catholic hospital)... Ten students were shot."

Obet Rawar, also from Elsham, said he feared more than 12 were injured and that some may have died because they were too fearful to seek medical help and had simply run away. "They ran to the forest, to wherever," he said.

Minister Giay said he helped two injured students and saw a five-year-old boy being treated in hospital for gun wounds. "They were shot. It was live bullets not rubber bullets, because they bled a lot and the bullets are still there."

Johannes Do, another witness, said that police opened fire again on Friday morning when they were carrying the bodies of their slain colleagues away from the university to the airport. "They shot to the left and right as they travelled all along the street" leading away from the university, Do said.

Locals have long complained that they do not get their fair share from the mine and that the company is guilty of significant environmental pollution.

Freeport McMoRan has also been under scrutiny over its payments to the military. According to a New York Times report in December, it paid 20 million dollars to high-ranking security officials between 1998 and 2004.