Jakarta – The police have vowed to tighten security at key foreign facilities in the capital following a violent attack Thursday morning at the office building where PT Freeport Indonesia is located.

The Jakarta Police spokesman Sr. Comr. Ketut Untung Yoga Ana said the police would deploy more officers to guard foreign premises, including embassies. "We will do our job proportionally," he told The Jakarta Post.

Earlier this week, the Islamic Defenders Front (FPI) attacked the US Embassy in protest of the US Supreme Court's 90-year-old sculpture that features the Prophet Mohammad and several other important lawgivers in history.

Head of the general crimes unit at the city police, Sr. Comr. Muhamad Jaelani, said the police had named 10 Papuan students as suspects in the attack in the lobby of Plaza 89 in Kuningan, South Jakarta. Three more students were allegedly implicated in the attack, but are still at large.

The office of PT Freeport Indonesia is located on several upper floors of the building. A total of 25 students from various universities here arrived at the building to protest against Freeport over clashes of local people and security officers during a demonstration Wednesday at the company's mine in Timika.

At about 3:30 a.m., 13 of them stormed into the lobby of the building by destroying the glass windows with flower pots. The other 12 remained outside.

There were only two security guards in the building, and they were unable to stop the students from entering, but managed to extinguish a fire set in the lobby by the students, who were armed with Molotov cocktails.

As city police officers began to arrive, 10 students hopped into a public minivan they had rented, while three others sped away on motorcycles. The students sought protection at the office of the Commission for Missing Persons and Victims of Violence (Kontras).

The police followed them to the rights activists' office and negotiated with Kontras, who will now act as their legal representatives. The activists agreed to hand the students over for arrest, said Kontras' executive Abu Said Pelu.

The students are all members of the Papua Students Council, according to the council chairman Yan Matua. "The attack was not premeditated. It was a spontaneous act triggered by accumulated disappointment toward Freeport and the Indonesian government, as we believe that Freeport paid the police..." he argued.

Freeport's mining operations remained suspended Thursday as residents continued to block access to the site for the second consecutive day. Freeport is trying to negotiate with the residents.

About 400 independent local miners set up barricades Wednesday at a road near the mine, which is owned by the local unit of US-based Freeport-McMoran Copper & Gold Inc., forcing the halt in production, after security forces attempted to evict them from the mine a day earlier.

The company's corporate communications senior manager Siddharta Moersjid said that the situation remained unchanged from Tuesday and that talks were being held between representatives of the protesters and Freeport officials.

The local miners have been demanding permission to sift through the waste pumped from the mine.

Meanwhile, in Papua's capital of Jayapura, some 300 people staged a protest at the local council building as well the Freeport office, demanding the company shut down its operation.

The incident near the mine is the latest snag in Indonesia for Freeport-McMoran, which has been under scrutiny for making payments to Indonesia's military for protection.

President Susilo Bambang Yudhoyono has instructed Energy and Mineral Resources Minister Purnomo Yusgiantoro to coordinate with the security minister to resolve the dispute, fearing a loss of national income if the mine stays shut.

The company is the largest taxpayer in Indonesia, reportedly contributing at least US$33 billion to government coffers in recent years.