BAGHDAD, Iraq - Insurgents killed three U.S. soldiers and an Iraqi civilian in separate attacks, and a militant group threatening to kill its Filipino hostage extended until Tuesday its deadline for Manila to agree to withdraw peacekeepers early.

The Philippine government previously rejected that ultimatum.

Also, Iraqi interim President Ghazi al-Yawer said his government will soon offer an amnesty to those who have fought against the U.S.-led coalition, a British newspaper reported today.

"We are offering an amnesty definitely, for people who have not committed too many atrocious acts," al-Yawer was quoted as telling The Financial Times. "Everybody except murderers, rapists and kidnappers."

He said the amnesty would be offered within "a couple of days."

The proposal was first mentioned earlier this month by a spokesman for interim Prime Minister Iyad Allawi, signaling the new government's desire to distance itself from the 14-month U.S.-led occupation of Iraq.

Also, Iraq's national security adviser, Mouwaffaq al-Rubaie, said Sunday the country would honor the Nuclear Nonproliferation Treaty and other international agreements banning the use of chemical and biological weapons.

"Iraq officially declares it will be a country free of any weapons of mass destruction," al-Rubaie said. "Iraq will never again resort to threatening its neighbors, as Saddam did."

Saddam Hussein's alleged possession of such weapons was one of President Bush's declared reasons for invading Iraq. The hunt for weapons of mass destruction has proved largely unsuccessful.

On Sunday afternoon, a roadside bomb exploded as U.S. patrol passed in Samarra, a hotbed of violence 60 miles north of Baghdad, killing two soldiers and wounding three others, the military said.

Earlier, a U.S. convoy was attacked in Beiji, 90 miles south of the northern city of Mosul. After a roadside bomb exploded, an enemy vehicle raced toward the convoy and fired at the soldiers, who shot back and killed the driver, the military said.

A soldier and a civilian traveling behind the patrol were killed. A second soldier was injured and evacuated. Thick black smoke enveloped the area from an oil tanker set ablaze in the attack.

The deaths came a day after four U.S. Marines were killed in a vehicle accident near Camp Fallujah in western Iraq. At least 875 service members have died since the military operations in Iraq began last year, according to the U.S. Defense Department.

Militants from a group calling itself The Iraqi Islamic Army-Khaled bin Al-Waleed Corps extended their deadline for the Philippine government to agree to withdraw its 51 peacekeepers. Initially, the group gave Manila until Sunday night to agree to a July 20 pullout or it would kill Filipino truck driver Angelo de la Cruz.