Lebanese authorities say four soldiers were killed Friday in ongoing fighting with Islamic extremists in a Palestinian refugee camp in northern Lebanon.

More than 130 people have been killed in four weeks of fighting between the soldiers and Fatah al-Islam militants at the Nahr al-Bared camp near Tripoli.

Tens of thousands of refugees have left the area, but many remain at the camp.

The U.S. State Department has alerted Americans to the ongoing fighting and political tensions in Lebanon and urged them not to travel there.

On Thursday, thousands of Lebanese attended the funeral in Beirut of anti-Syrian lawmaker Walid Eido, who was killed in a car bomb blast on Wednesday.

Mourners chanted anti-Syrian slogans in the funeral procession, led by Saad Hariri and other leaders of the anti-Syrian majority bloc in parliament.

Hariri, the son of the slain former Lebanese prime minister Rafik Hariri, told the funeral service the criminals responsible for the bombing will be punished.

The bombing also killed Eido's son and eight other people. Allies of Eido have blamed Syria for the attack. Syria condemned the bombing and denied responsibility.

The United States, the United Nations and France also condemned the killing.

Eido was the seventh prominent anti-Syrian figure to be murdered in Lebanon by bombs or gunfire since 2005.

Some information for this report was provided by AFP and Reuters.