FIERCE fighting engulfed the once serene mountain resort of Swat yesterday, with thousands of civilians trapped as the Pakistani army launched an all-out offensive against the Taliban.

In Swat’s main town of Mingora, now controlled by the Taliban, residents described a scene of terror. Taliban positions were heavily shelled, food and water were running low and electricity and most telephone lines had been cut.

Some described how they were left cowering inside their homes, praying for survival as fighter jets screeched overhead. An army curfew and Taliban threats prevented them fleeing.

The army said it had killed 55 more Taliban fighters in Swat yesterday, bringing the total to more than 200 since the operation began. Hundreds of civilians were feared dead. The provincial government, claiming that hundreds of thousands more were flooding down from the mountains in search of safety, said it could not cope.

Yusuf Raza Gilani, Pakistan’s prime minister, said the military was fighting “for the survival of the country”.

The Taliban placed land mines on the main roads out of Mingora and seemed intent on preventing people from leaving. An army spokesman said the extremists were deploying “innovative” explosive devices, such as pressure cookers packed with nails, to attack patrols.

Heavy artillery fire could be heard yesterday in Saidu Sharif, just over a mile from Mingora. One resident said there had been heavy casualties but people were unable to move out of their houses to tend the injured or to bury or count the dead.

A medical student who stayed in Mingora to help treat the wounded told The Sunday Times: “The electricity has been suspended for a week. The health situation is very bad; there are only three doctors in the main district hospital. Please keep praying for us.”

He said many inhabitants had remained in their homes because they feared their possessions would be looted. “People who left their homes, all their stuff was taken, even the plates and spoons were not spared by both army and Taliban so people are afraid of leaving.”

The student added that the army seemed determined to flush out the militants. “For the first time, they are killing Taliban,” he said. “Till now it was just a show-off to the world in which only civilians were killed.”

Afrasiab Khattak, a Pakistani senator who acted for the North West Frontier’s provincial government in a controversial peace agreement in which the Taliban won effective control of the valley and imposed sharia, or religious law, last month, highlighted concerns for a “densely populated area”.

“The Taliban came down from the mountains when the military operations started and are using the people as human shields,” he said.

Residents reached by telephone in the village of Matta, 12 miles outside Mingora, said they were terrified of being caught in the crossfire but could not leave because of the curfew imposed by security forces and the Taliban’s claims that they had mined surrounding roads.

“Every minute brings a message of death to me and my family,” said Muhammad Khan, under siege with 25 family members. “We’re running out of food and water. We can hear the thud of artillery and mortar shells and the sound of helicopters. We are at the mercy of God now. Only he can save my family.”

John Butt, a Muslim chaplain at Cambridge University who set up a radio station in Swat last year, said he was hearing similar tales. “In the village where I lived in Madyan district they tell me the military are entrenched and the militants [are] in the next valley so they, the civilians, are being caught in the crossfire,” he said.

He added that he was extremely worried about the 10 staff of his radio station in Mingora. “There is no electricity or phone and I haven’t heard from them for several days,” he said.

The military operation could drive more civilians to support the militants, he warned. “It looks good to say ‘We’re fighting the militants’, but it’s the civilians who are the victims. In that part of the world if you kill 10 civilians, you make 100 enemies.”

Those who could escape were arriving at hastily created refugee camps on foot or by donkey cart or car. The displacement of much of the 1.5m population of Swat, plus more refugees from the neighbouring area of Buner, has left authorities struggling to cope. All leave has been suspended and doctors and welfare staff are working round the clock.

“We’re calling upon the federal government and the international community to help,” said Khattak. “We need money, food, tents and water. We can’t cope on our own.”

Pakistan had little choice but to attack the Taliban, led by the radical cleric Maulana Fazlullah, after Islamabad came under intense international pressure to show which side it was on.

Swat is just 100 miles from the capital and the battle is a pivotal moment for the government of President Asif Ali Zardari. Pakistan’s future as a functioning state could be in the balance if it cedes yet more territory to the militants.

“The Pakistan government has to show it’s a force to be reckoned with,” said Lord Malloch-Brown, the Foreign Office minister. “It has to show it’s got a grip both politically and militarily. Let’s see what they can do.”

In Washington, President Barack Obama’s administration has made clear that it does not trust Pakistan – which has been receiving $1 billion a year in US aid for its support in the war on terror – to act decisively against the Taliban.

General David Petraeus, head of US Central Command, told The Wall Street Journal yesterday that Pakistan had displaced Afghanistan as Al-Qaeda’s stronghold. “It is the headquarters of the Al-Qaeda senior leadership,” he said.

US concern about who controls Pakistan intensified last month when Islamabad approved the agreement to introduce sharia in Swat.

In Washington it was seen as an act of appeasement. Rather than laying down their arms as promised, Taliban forces moved into Buner, just 60 miles from the capital, with no apparent government resistance.

Hillary Clinton, the US secretary of state, infuriated Pakistan by saying it was “abdicating to the Taliban and to the extremists” and that the situation posed a “mortal threat” to the world.

America’s anger was made clear to Zardari when he flew to Washington last week to meet Obama and his administration. This time the threats struck home. On Thursday night the Pakistani army ordered 15,000 troops into Swat to fight an estimated 4,000 militants.

General Ashfaq Kayani, the chief of the army, told his top commanders that he would “employ requisite resources to ensure a decisive ascendancy over the militants”.

“The army are serious this time,” said Khattak, the senator. He added that he was confident the military operation would succeed.

Khattak warned that Taliban control of Swat was only part of the problem. “The media has focused on Swat but, even if the Taliban are cleared from there, they won’t disappear. They will just move to their bases . . . They have a parallel state.”

According to reports from Mingora last night, the Taliban were shaving off their beards and trying to hide among locals to escape from the valley.

A US drone attack in the area of Waziristan yesterday killed five militants, despite fresh pleas from Pakistan for an end to such operations.

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