Indonesia's military dropped paratroopers Tuesday in Aceh (search) as part of a major offensive against separatist guerrillas who defied government demands to disarm, while governments around the globe urged Jakarta to restarts talks with the rebels.

The troops are part of a 30-000-member force trying to crush 5,000 poorly armed guerrillas in a dense, mountainous forest. The sides have been fighting since 1976, making this one of Asia's longest-running conflicts.

The opening of the offensive Monday signaled a return to military confrontation after the breakdown of a Dec. 9 cease-fire between the government and the Free Aceh Movement (search).

The United States, Japan, Australia and members of the European Union said that talks aimed at securing a deal for Aceh's regional autonomy did not go far enough.

Officers said 12 rebels had been killed or captured so far in the operation, which was ordered after rebels refused to drop their independence bid and disarm during peace talks in Tokyo over the weekend.

"We have ongoing operations in the south and north of the region," Aceh Military chief Maj. Gen. Endang Suwarya told The Associated Press.

A peace accord -- which envisioned autonomy, rebel disarmament and military withdrawals -- unraveled in recent months following violence and mutual recriminations in the province 1,200 miles northwest of the capital, Jakarta. More than 12,000 people have been killed in the decades of fighting.

President Megawati Sukarnoputri (search) spared no time ordering a crackdown after rebels refused to honor a government-imposed deadline for laying down weapons and abandoning their demand for independence.

Five rebel negotiators also were arrested and accused of carrying out a series of recent bombings in Indonesia.

A presidential decree authorized six months of military rule in Aceh, giving authorities wide powers to make arrests and limit movements in and out of the province.

Nervous residents braced for harsher strikes and heavy casualties.

"The rebels will hide behind the civilians, and how will the army tell the difference? Many people will die," a resident named Mawarni said after praying at Banda Aceh's main mosque.

The government estimated that the number of refugees in Aceh will balloon to 100,000 from the current 5,000.

On Monday, attack planes droned over the provincial capital of Banda Aceh and fired rockets at a suspected rebel weapons cache at a hillside base. The blasts destroyed an abandoned chicken coop and farmers' huts near empty villages surrounded by palm-fringed rice fields.

Six C-130 Hercules transport aircraft released 458 parachuters over an airstrip close to Banda Aceh, Maj. Gen. Erwin Sujono said.

More than 600 marines landed from one of 15 warships off the province's northern coast, an area with a heavy concentration of rebels, Sujono said.

Aceh, on Sumatra island's northern tip, was once an independent sultanate and has a long history of defiance, beginning with a Dutch colonialist invasion in 1870.

The Acehnese were at the forefront of Indonesia's fight for independence during the 1940s. When Indonesia declared independence in 1945, Aceh was promised autonomy but never got it -- the first of many broken promises by Jakarta that triggered a series of Acehnese rebellions.

Many Acehnese in the world's most populous Muslim nation want to be governed by a brand of Islam much stricter than that practiced in the rest of Indonesia.

But the ongoing crackdown is not only about keeping the vast archipelago nation in one piece. Extortion, drug running and arms smuggling have allowed elements on both sides to profit from the conflict.

Also at stake are huge reserves of oil and gas that locals want to keep for themselves.

Weekend talks in Tokyo were arranged hastily under pressure from international donors alarmed by the prospect of renewed fighting. Even as the two sides talked, thousands of Indonesian troops massed in the province.

U.N. Secretary-General Kofi Annan issued a statement saying he was deeply concerned about reports of new fighting in Aceh. He said the conflict can only be resolved peacefully and urged both sides to resume negotiations.

The European Union, Japan, the United States and the World Bank issued a joint statement Monday saying they "deeply regret" that the two sides "failed to seize the unique opportunity before them."

Rebel leader Malik Mahmud said he believed the Indonesian government was "looking for a way to declare war" and had no intention of compromising.