Syria's army and intelligence agents on Thursday completed the first phase of their pullback to eastern Lebanon and Syria, while a top Lebanese security chief said he and other officials were willing to stand trial to clear allegations of negligence in the assassination of former Prime Minister Rafik Hariri (search).

The Syrian withdrawal comes ahead of Tuesday's summit of Arab leaders in Algeria. Syrian and Lebanon agreed earlier this month that Syrian troops and intelligence agents would redeploy in the eastern Bekaa Valley (search) or withdraw to Syria before the end of the month.

"They have finished their redeployment," a senior Lebanese army officer told The Associated Press on condition of anonymity. He refused to give further details, saying a statement would be released within 48 hours.

Of the 14,000 troops that were in Lebanon, at least 4,000 crossed into Syria in the past week and the rest remain in the Bekaa. Syrian President Bashar Assad (search) promised to bring the troops back home in the second phase of redeployment, for which no date has been set.

Syria began the redeployment on March 8 after coming under international pressure to withdraw from Lebanon following the Feb. 14 assassination of Hariri in Beirut, which sparked weeks of anti-Syrian demonstrations.

The Lebanese opposition accused Syria and the Lebanese government of being behind the assassination and have called on Lebanese security chiefs to resign, alleging negligence. Both governments have denied the charges.

Jamil Sayyed, head of the powerful General Security Department and a close aide of President Emile Lahoud (search), said Thursday he and other officials were willing to stand trial to clear their names.

"All the heads of security institutions are ready for trial and accountability," he said at a news conference. "We have no secrets to be embarrassed of."

He lashed out at opposition demands for the resignation of security chiefs, indicating they will not step down. He said he was starting legal proceedings to clear his name and those of other security chiefs, though he said he hadn't consulted the others.

Sayyed, a retired army major general who has been in the post since 1998, is considered one of Lebanon's most influential security chiefs. His General Security Department, which is part of the Interior Ministry, is in charge of border points, issuing passports and censorship of publications.

Since his appointment by Lahoud, the department has taken on additional significance and had become the nerve center of the Lebanese security and intelligence network.

The withdrawal of the Syrian intelligence agents has been a key demand of the Lebanese opposition, which sees them as the main face of Syria's long domination of Lebanon. Though Syria had thousands of troops in Lebanon, it was usually the intelligence agents who carried out arrests and set up roadblocks and to whom Lebanese had to turn to get commercial permits and even settle disputes.

Syrian intelligence agents evacuated their Beirut head office Wednesday, while in the northern city of Tripoli, Lebanon's second largest, the last two offices were cleared out early Thursday, witnesses said.

Intelligence officers remain in the Bekaa Valley town of Anjar, which has been the Syrian intelligence headquarters in Lebanon since 2000.

The pullback comes amid increasing demands from the United States and the Lebanese opposition, which orchestrated a gigantic demonstration Monday of about 1 million people in central Beirut.

President Bush has called on Syria to withdraw completely before Lebanon's parliamentary elections in April and May.