U.N. troops killed as many as 60 militiamen in a stepped-up campaign to clear northeastern Congo (search) of rogue gunmen who have preyed on residents and are suspected in the recent slaying of nine peacekeepers, U.N. officials said Wednesday.

The peacekeepers, backed by an attack helicopter and responding to fire, killed more people than in any other operation during their six-year mission in Congo.

Tuesday's gunbattle between 242 Pakistani peacekeepers and militia fighters broke out at a heavily fortified militia camp near the village of Loga, 20 miles north of Bunia (search), the capital of the lawless Ituri province, said Col. Dominique Demange, spokesman for the U.N. forces in Congo.

"While on operation we were fired upon, so we immediately responded," he said.

Peacekeepers returned fire and called in an attack helicopter, Demange said. He added that between 50 and 60 militia members had been confirmed dead.

Two peacekeepers were wounded and evacuated to South Africa, U.N. spokeswoman Eliane Nabaa said.

The operation marked an aggressive shift in the way the world body is tackling its mission to shepherd Congo toward peace and stability after years of accusations that U.N. peacekeepers (search) have been ineffective.

The militia, which belongs to the ethnic Lendu political party Nationalist and Integrationist Front, has been terrorizing villages of the rival Hema tribe for months. Tribal fighters have killed dozens of people, looted and burned homes and forced more than 70,000 people to flee to the hills since December.

The United Nations suspects the same militia is responsible for killing the nine Bangladeshi peacekeepers in a well-executed ambush on Feb. 25.

Diplomats and U.N. officials on Wednesday made clear their support for the peacekeepers' action, which targeted a militia that had slain nine Bangladeshis in an ambush on Friday. They also insisted that the peacekeepers were carrying out their mandate of protecting civilians in a volatile area.

"The U.N. has traditionally kept peace, it hasn't done war fighting, but when you're confronted with people who are fighting you, you have to exercise self-defense and take them out," Britain's U.N. Ambassador Emyr Jones-Parry said.

There were signs the slain Bangladeshis survived the ambush and were then executed.

Richard Grenell, spokesman for the U.S. Mission to the United Nations said the U.S. mission had been briefed by the U.N. that the nine were shot at point-blank range.

"This group continues to loot, kill and rape these people, making life miserable," said Nabaa. "It's time to put an end to this militia."

The violence is taking place against a stunning backdrop of sweeping, grassy hills and a patchwork of farms and thatched huts.

"Our forces will keep putting pressure on the ground until these militia are dismantled entirely," said Gen. Jean-Francois Collot d'Escuries, chief of staff for U.N. troops in Congo.

In January, hundreds of peacekeepers were dispatched to several areas of the isolated, territory to provide security and allow humanitarian groups to distribute food and medicine.

But following the slaying of the nine U.N. soldiers, the United Nations announced it was suspending humanitarian assistance to 54,000 people due to increased violence.

For several years, U.N. peacekeepers in Congo have been accused of being ineffective.

In 2003, a small contingent of U.N. Uruguayan troops in Bunia were quickly overrun when Hema and Lendu militia fought for control of the town, killing more than 500 people.

The United Nations drew stiff international criticism for allowing the deaths, many of which were execution-style murders carried out by rival teenage gunmen. The United Nations blamed a weak Security Council mandate that only permitted them to protect U.N. staff.

The U.N. Security Council toughened the mandate months later, allowing them to protect civilians. However, they were criticized again in June 2004 when renegade Congolese troops seized the lakeside town of Bukavu in the east, mostly while U.N. troops stood by.

The fall of Bukavu sparked riots in the capital.

The U.N. mission in Congo is also embroiled in a major scandal in Bunia after many young girls living in displaced camps accused peacekeepers of raping them, or trading sweets and money for sex.

The young Lendu fighters — who often wear wigs and women's dresses in battle because they believe it will protect them from harm — are accused of massacring thousands of Hema in macabre pogroms over the years, often feasting on the still-warm hearts and livers of the dead.

Hema militia often respond by waging murderous attacks on Lendu villages.

Since 1999, fighting in Ituri between Hema and Lendu militia has killed more than 50,000 and forced 500,000 to flee their homes, U.N. officials and human rights groups say.

The Ituri conflict follows Congo's five-year, six-nation war that killed nearly 4 million people, according to aid groups. The war ended in 2002 with the formation of a transitional government that has struggled to extend its authority to the long-ungoverned east.