Over 600 victims of the mud-volcanoin East Java province staged rally outside the Presidential palace today, demanding a full payment of the rest of 80 percent compensation, which has been delayed by a firm.

The mud volcano, which erupted in May 2006 near Indonesia's second-biggest city of Surabaya, had submerged 12 villages as well as displaced more than 50,000 people.

Scientists have said that energy firm PT Lapindo Brantas' drilling for a gas exploration well caused the mud volcano. But the firm has denied it, saying the disaster was set off by tectonic activity.

The Indonesian government has ordered the firm to pay 3.8 trillion rupiah (about US$310.2 million) in compensation to the victims due on Dec. 1.

The protester marched from the biggest most of Istiglal in the capital and gathered outside the Presidential Palace.

They requested to meet President Susilo Bambang Yudhoyono, demanding for a full payment of the rest 80 percent of the compensation as it has already approved by the company.

"80 percent paid Cash, No Installment," said a banner of the protesters.

The victims rejected another resolution offered by Public Minister Joko Kirmanto yesterday in which the payment of the rest of compensation would be carried out gradually.

"We want to meet President Susilo and ask for full payment of the compensation," said a demonstrator outside the palace.

Over 300 policemen were on guard outside the palace.

Lapindo is politically linked to the Bakrie Business Group, controlled by the family of Indonesian Coordinating Minister for People Welfare and Poverty Alleviation Aburizal Bakrie, who earlier this year was named as Indonesia's richest man.

The firm is due to pay 80 percent of the compensation by December after paying 20 percent in 2007.