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

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 gun battle 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, the capital of the lawless Ituri province, said Colonel 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, Colonel Demange said. He added that between 50 and 60 militiamen had been confirmed dead.

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

The operation marked the first time such a large number of militiamen had been killed since the U.N. Security Council widened the Congo mission’s mandate in October to counter accusations that U.N. peacekeepers have been ineffective. It also sent thousands more troops to Congo.

The new mandate gave the peacekeepers the power to deploy to potentially volatile areas. They could deter the use of force, protect civilians under immediate threat of violence, and seize illegal weapons.

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 February 25.

Diplomats and U.N. officials yesterday 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.

Late yesterday, the United Nations said the nine peacekeepers were shot at point-blank range, and their bodies were stripped of all weapons, ammunition, uniforms, and all equipment.

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