A suicide bomb attack at a luxury hotel in the Pakistani city of Peshawar has claimed the lives of at least 15 people and left dozens injured. The dead include two United Nations workers, while many foreigners are among the injured.

Gunmen shot their way through the outer security barrier of the Pearl Continental hotel on Tuesday evening and rammed a van packed with explosives into the five-star hotel, causing massive destruction. One section of the building is completely destroyed.

Peshawar is situated near the Swat valley in the north-west of the country where the recent government offensive against the Taliban was concentrated. It is the seventh deadly bombing to hit the city in a month as fears grow that Taliban militants are exacting revenge for the government action.

A UN official said two UN workers, a Russian man and Philippine woman, were among those killed in the Tuesday night assault on the Pearl Continental, a hotel popular with VIPs and foreigners visiting the capital of North West Frontier Province.

Taliban militants have stepped up attacks in cities since the army launched a campaign in April to clear  Islamist fighters from a stronghold in Swat and other parts of northwest Pakistan.

Massive bomb
The force of the blast blew out all its  windows, and caused several concrete walls and a section of floors to collapse on the hotel's front side.

Senior police official Abdul Gafoor Afridi said 64 people were wounded. Hospital workers said many suffered multiple injuries.

Militants had shot their way into the Peshawar hotel forecourt and exploded a truck bomb in front of the lobby, evoking nightmarish memories of the attack on the Marriott hotel in Islamabad last September that killed 55 people.

"I was in the Chinese restaurant when we heard firing and then a blast. It was totally dark and people started shouting and running," hotel waiter Ali Khan told Reuters.

Police said the bomb contained 500 kg (1100 lb) of explosives, a similar size to the bomb at the Marriott.

The mangled truck used in the attack could be seen several feet away from the crater caused by the explosion.

There was no claim of responsibility, but the Taliban have warned of retaliation because of the Swat offensive, and there has been a new trend in militant tactics towards using gunmen in support of a suicide bomber.

There are expectations the army will turn its attention to other Taliban strongholds, like the South Waziristan tribal region bordering Afghanistan, once Swat has been dealt with.

Those areas have provided important refuge for Taliban fighters who have been ramping up their insurgency in Afghanistan.

Shock
The government's military effort has been helped by a shift in public opinion in support of the use of force.

That support might ebb if the welfare of some 2.5 million people displaced by the conflict in the northwest is mishandled. U.S. officials are rallying international support to help Pakistan cope with the humanitarian crisis.

The military says troops have cleared most of Swat, but soldiers are encountering pockets of resistance.

In all, the army says more than 1300 militants and 105 soldiers have been killed in the offensive. There has been no independent confirmation of the figures.

The United Nations is heavily involved in providing relief for the people who have fled their homes to escape the conflict in Swat, and about a dozen UN staff were staying at the hotel.

A German woman also working for the UN children's fund, and a British and a Nigerian man were wounded, according to top city administrator Sahibzada Anis.

UN Secretary-General Ban Ki-moon condemned the attack: "Once again, a dedicated staff member of the United Nations is among the victims of a heinous terrorist attack which no cause can justify," Ban's press office said in a statement issued before confirmation fo the second UN death.

The hotel manager was among the missing, according to Jameel Khawar, a spokesman for the Pearl Continental.

Less than a third of the hotel's 150 rooms were occupied. While rescuers searched the ruined hotel, a bomb disposal squad on Wednesday sifted through the site of the blast, which destroyed dozens of cars parked in the forecourt.

*Reuters, ANP