Media reports said Shehade was moderately injured in the explosion, which went off as his car drove by the village of Rmaileh, near the southern port city of Sidon. He was taken to the Hammoud hospital in Sidon, and hospital officials said his condition was stable.

Security officials said four aides and bodyguards were killed and another five were wounded in the attack.

Shehade is deputy chief of the intelligence department in Lebanon's internal security force.

Interior Minister Ahmed Fatfat said Shehade was involved last year in the arrest of four generals accused of involvement in ex-Premier Rafik Hariri's assassination. The four are Brig. Gen. Jamil Sayyed, Brig. Gen. Ali Hajj, Brig. Gen. Raymond Azar and Brig. Gen. Mustafa Hamdan.

Security sources said he was also involved in the interrogation of several witnesses in the Hariri probe, including Syrian intelligence operative Hussam Hussam.

The sources said Shehade had received threats because of his work in the Hariri probe.

Shehade's assassination attempt came two weeks before Chief U.N. investigator Serge Brammertz is due to submit his second report on the Hariri murder.

Security officials said a roadside bomb was detonated by remote control as Shehade's two-vehicle police convoy traveled on a highway between two bridges.

Fatfat told LBCI that the blast was caused by a roadside bomb loaded with nails. He said it targeted the car normally driven by Shehade, who was traveling in the other vehicle at the time.

Shehade's convoy was riddled with shrapnel and TV footage showed at least one bloodied man slumped on his seat in one of the cars. Police sealed off the area and began an investigation.

Top picture: A Lebanese military policeman (R) prepares to evacuate a wounded Lieutenant Colonel Shamir Shehade after he was wounded in a bomb attack near Sidon

A Lebanese soldier and a policeman inspect the damaged car of a senior Lebanese intelligence officer near Sidon city, southern Lebanon, September 5, 2006. The senior Lebanese intelligence officer, identified as Colonel Samir Shehadeh, was wounded by a bomb which exploded in the car on Tuesday, police said.

Sources: Naharnet, AP, Reuters