A powerful explosion late Monday rocked a shopping center and hotel in the Zalka neighborhood of north Beirut, injuring at least three people and causing extensive damage, security officials said. Heavily armed Lebanese soldiers cordoned off the area, punching and hitting journalists to keep them back. Two workers helped a black-clad, veiled woman down the glass-covered front stairs of the Promenade Hotel. She appeared shaken but not injured. Shattered glass filled the hotel lobby, but no residents were hurt.

Brigadier General Darwish Hobeika, Lebanon's Civil Defence Corps commander told Lebanese Broadcasting that two people were lightly injured and one civil defence rescuer was hurt. The explosion shattered the windows of several apartment buildings and blew shutters off dozens of luxury boutiques in the neighborhood. Black smoke billowed high in the night sky, though there was no fire. Aluminum siding and roofing in the shopping center buckled. The state-run National New Agency estimated the explosion was caused by 20 kilograms of TNT.

After ambulances and civil defence trucks arrived, security forces were seen rounding up several suspects, including five men with their hands tied behind their backs who were taken to a military vehicle.

Zalka Mayor Michel Murr told the Lebanese Broadcasting Co. that the bomb was placed in an open area between the Musa Shopping Center and the Promenade Hotel, which was packed with tourists. A busy Starbucks coffee shop is situated across the street.

Zalka, on the Mediterranean coast, is a mixed residential and commercial area on a main street that leads to Lebanon's Christian heartland. The area has several cafes — including the Starbucks coffee shop — as well as restaurants and other nightspots that were full of patrons.

The explosion was the latest in a string of bombings that have killed or wounded politicians and other prominent figures in Lebanon since the February assassination of former Prime Minister Rafiq Hariri. Bombs have also targeted commercial and industrial centers.

The bomb that killed Hariri took 20 other lives, and explosions since then have killed at least six people, including a prominent politician and an anti-Syrian journalist. More than 50 people, including Lebanon's Defence Minister, have been injured. The most recent explosion occurred on July 23 rd in a busy Christian neighborhood, just hours after Secretary of State Condoleezza Rice made a brief, unannounced visit to Beirut. The blast wounded 12. On July 12 th, a car bomb struck the motorcade of Lebanon's pro-Syrian defence minister, Elias Murr, in a Christian suburb north of Zalka. Murr was wounded and one person died.

Hariri's assassination on a Beirut street, which many people blamed on Syria, triggered anti-Syrian protests at home and international pressure that eventually ended three decades of Syrian domination of Lebanon with the withdrawal of the Syrian army. The latest bombing was sure to intensify political tension between anti-Syrian Lebanese, who won the parliamentary elections in May and June, and pro-Syrian politicians. The tensions are fueled in part by the unfinished UN-mandated investigation into Hariri's assassination and media leaks about alleged suspects and their involvement.

At the U.N. on Monday, Undersecretary-General for Political Affairs Ibrahim Gambari said UN investigators are making progress in their investigation of Hariri's assassination but need more time to complete their work. The investigation formally began on June 16 th and is led by a German prosecutor, Detlev Mehlis, who is expected to return to New York in September to report to the UN Security Council.