ISLAMABAD: Pakistan said Tuesday that soldiers rescued 80 kidnapped staff and students in a sting operation during a fierce battle, one day after they were snatched by masked Taliban gunmen.

The brazen abduction in a wild part of the northwest, which targeted staff and students from an army-run cadet college, had sparked increased fears of a widening backlash to a more than one-month offensive against the Taliban.

The military said all 71 cadets and nine staff were rescued when militants were moving them from the lawless tribal areas of North Waziristan to South Waziristan, where Washington accuses Al-Qaeda of plotting attacks on the West.

"The army established checkposts and all the routes were blocked. After a fierce fight the army was able to recover them," the army said.

Officials near the college in Razmak said the students are aged 15 to 25 and were not training for the army.

They had been held up at gunpoint on Monday in the province close to Afghanistan where Pakistan has pressed an assault against the Taliban for more than a month amid fears the rebels were gaining ground in the country.

"We tried to secure the release through negotiation. After that, we were compelled to launch a military operation," a military spokesman said in Peshawar, the main city in northwest Pakistan.

No soldiers or civilian casualties were reported in the sting operation.

Tribal elders and government officials had been locked in talks overnight on efforts to secure the release of the students and staff.

The students had been heading to the town of Bannu after the college closed for the summer, Bannu town police chief Iqbal Marwat told AFP, adding: "They have been kidnapped by Taliban militants."

There had earlier been some confusion as to exactly how many students had gone missing, with numbers ranging from 20 to 100.

The incident fuelled already growing fears of revenge attacks for Pakistan's determined offensive, which has garnered widespread public support in the Muslim country for the first time and has upped attacks on civilians.

More than 80 people have been killed in bomb blasts across the country since the operation was launched on April 26, including two people killed in a car bomb in the garrison town of Kohat, also in northwest Pakistan, on Monday.

The military campaign is now in a sixth week since Taliban fighters advanced to within 100 kilometres (60 miles) of Islamabad, flouting a deal to put three million people under sharia law in exchange for peace.

The United States, which has strongly backed the operation, is sending special envoy Richard Holbrooke to Pakistan on Wednesday to examine the humanitarian crisis first hand and meet some of the displaced.

UN officials say up to 2.4 million people have fled the fighting, in what has been called the largest internal displacement in more than half a century.

The United States has announced 110 million dollars in emergency aid, on top of a multi-billion-dollar package working its way through the US Congress to help Pakistan root out extremism, a top US foreign policy priority.

Pakistan has said that more than 1,200 militants and around 90 soldiers have died since the operation was launched at the end of April.