Updated

Scores more foreign soldiers landed in East Timor on Wednesday to bolster a force struggling to stop mob violence in the capital, and Australia said a long-term international security force may be needed to get the country back on its feet.

Much of Dili was peaceful, but sporadic gunfire rang out in some parts of the city, and smoke rose from burning buildings. In one neighborhood, a group of young men broke into several houses, kicking in the doors.

Clashes also broke out between gangs of machete-wielding youths near the airport, witnesses said. At least one person seriously hurt. Foreign troops rushed to the site.

CountryWatch: East Timor

Some 2,000 Australian military personnel — 1,300 front-line troops and hundreds of support staff — began arriving late last week and were guarding key facilities and conducting limited street patrols.

New Zealand troops began arriving Wednesday, deploying from military cargo planes carrying packs and rifles. Some 160 were expected by day's end. More than 330 Malaysian troops are in place and 120 Portuguese paramilitaries are due by the end of the week.

What started with sporadic clashes last week between dismissed former soldiers and government troops has spiraled into open street violence in Dili that has fluctuated in intensity from day to day, heightening the sense of instability. At least 27 people have died.

President Xanana Gusmao has invoked emergency powers, and the country's troops are mandated to open fire in severe circumstances to control the rampant lawlessness that has plagued the city for almost a week.

The international force has had only a limited effect since it started arriving. Leaders insist new powers to detain, not just disarm, suspects will help but concede they don't have full control.

On Wednesday, an Australian patrol arrested a gang of nine young men, seizing machetes and other primitive weapons and marching them in line into custody. But gangs that stopped fighting when patrols arrived simply resumed after the troops left, Australian commander Lt. Col. Michael Mumford told Australia's Nine Network television.

Brig. Mick Slater, the Australian commander in Dili, told reporters on Wednesday his troops had not fired a shot since arriving, though they released tear gas from a helicopter on Tuesday to disperse a gang.

In Canberra, Australia's military chief, Air Chief Marshal Angus Houston, said he expected the peacekeeping mission to last at least six months.

Defense Minister Brendan Nelson suggested that a semi-permanent international security force might be needed to help ensure "the political, financial, legal and social reconstruction of East Timor over the near and longer term." He said Australia could lead such a force.

The violence is the worst in East Timor since its bloody break from Indonesia in 1999, which paved the way for full independence in 2002 after years of U.N. administration. It remains one of the world's poorest countries, and is dependent on foreign aid.

Fifteen major aid donors on Wednesday urged groups responsible for the crisis to stop their feuding.

"As the world's newest nation, (East) Timor had made great strides in recovering from the devastation of the 1999 crisis," the donors said in a statement. "These gains ... must not be lost to violence and conflict."

The statement was released on behalf of Australia, the United States, Britain, the EU, theAsian Development Bank, International Monetary Fund, World Bank and eight other countries.

Pope Benedict XVI also appealed Wednesday for an end to the violence in the Roman Catholic country.

"My thoughts now go to the dear nation of East Timor, in these days in the grip of tensions and violence, which have caused death and destruction," the pontiff said in his weekly address in St. Peter's Square.

Gusmao took over the government's security powers late Tuesday in a bid to break a deadlock that has paralyzed the government and fueled the unrest. He appealed to people to surrender illegal weapons and explosives to foreign peacekeepers, and to cooperate with identification checks and surveillance operations.

The violence was triggered by the dismissal in March of 600 soldiers from the 1,400-member army who were striking over alleged discrimination in the military. Rebel leader Maj. Alfredo Reinado said Gusmao's announcement wouldn't end the crisis because Prime Minister Mari Alkatiri — whom the rebels accuse of discrimination — had not been fired.

"The prime minister should go," Reinado told The Associated Press by telephone from a rebel stronghold in the hills surrounding Dili. "Why doesn't he just leave? Do more people need to be killed?"

The conflict also pits East Timorese from the "east" — perceived to be pro-independence — against those from the "west," believed to be sympathetic to Indonesia, the former occupier. Many pro-Indonesian militiamen slaughtered an estimated 1,500 civilians and burned down much of Dili in the last days of Indonesian rule before an Australian-led force restored order.