Gunmen attacked two more trucks carrying NATO supplies to Afghanistan, burning them and killing one driver, a Pakistani official said Monday. It was the fourth such attack since Friday.
It came on the same day as the Pakistani Taliban' claimed responsibility for a pre-dawn attack Monday on tankers carrying fuel to Afghanistan for U.S. and other NATO forces. The Taliban also threatened more attacks.
Mohammad Hashim, a government official in the southwest district of Kalat, said the two gunmen on a motorcycle opened fire on the trucks Monday afternoon, then torched the vehicles.
Hashim said the gunmen fled following the attack, which occurred about 100 miles south of the region's main city of Quetta. It was not clear who the attackers were.
In the early morning attack, about a dozen militants peppered vehicles parked at a truck stop on the outskirts of the capital Islamabad with automatic gunfire. Some 20 trucks went up in flames and four people were killed and seven injured, authorities said.
Last Thursday, , including a helicopter attack that killed three Pakistani soldiers.
Traffic has since been backing up at various points along the route from the southern port city of Karachi to the crossing at Torkham — where scores of trucks remain stranded and vulnerable to attack in the volatile Khyber Pass.
Although Pakistan says the blockade will soon be lifted, the latest attacks and the Taliban threat seemed certain to raise the stakes in the closure, which has exacerbated tensions between Washington and Islamabad.
"We are trying our best to protect the places where are vehicles have accumulated, and we are not dispatching any more trucks from Karachi for now," said Shakir Khan Afridi, president of the Khyber Transport Association, a major umbrella organization representing some 7,000 truckers.
Islamabad lies about 120 miles from Torkham.
The Pakistani Taliban, which last week threatened more attacks on the supply lines, claimed responsibility for the pre-dawn attack in a telephone call to an Associated Press reporter.
Spokesman Azam Tariq said a new wing of the group had been created to strike the convoys and that the attacks "would continue until the supplies are completely stopped."
Trucks moving supplies from Karachi through Pakistan into Afghanistan make frequent stops along the way for their drivers to rest along the several-day journey, and Kalim Imam, police chief of the capital Islamabad, said it was impossible for police or local authorities to protect them all the time.
"This entire thing is very vulnerable for such attacks," he said.
While attacks on convoys in Pakistan give militants a propaganda victory, coalition officials say they do not result in shortages in Afghanistan.
The Torkham border crossing is used to bring fuel, military vehicles, spare parts, clothing and other non-lethal supplies for foreign troops. Pakistan's other main route into landlocked Afghanistan, in Chaman in the southwest, has remained open. NATO also receives supplies via the Central Asian states north of Afghanistan.
Afridi said, however, that some trucks on their way to Chaman have also been unable to get through due to the massive flooding in the region — which left millions homeless and destroyed thousands of miles of roads.
"On that route too, container trucks and oil tankers are stopped at different points but not in very large number," he said.
While NATO and the United States have alternative supply routes into Afghanistan, the Pakistani ones are the cheapest and most convenient. Most of the coalition's non-lethal supplies are transported over Pakistani soil after being unloaded at docks in Karachi. There are some 140,000 international forces currently in Afghanistan.
On Friday, a day after the closure of the Khyber Pass route to NATO and U.S. traffic, there were two attacks on oil tankers headed to the country, one of which was claimed by the Pakistani Taliban.
The Pakistani Taliban are the country's largest militant group. Based in the northwest, it has claimed responsibility for scores of suicide bombings against Pakistani government and security targets, as well as Western ones. The group has ties with the Taliban movement in Afghanistan that is fighting the U.S.-backed government there.
Striking the supply line now gains the group more media attention than normal and makes the mission in Afghanistan appear vulnerable.
While attacks on convoys in Pakistan give militants a propaganda victory, coalition officials say they do not result in shortages in Afghanistan. Hundreds of trucks still cross into Afghanistan each day.
Some attacks are believed to be the work of criminals, who can sell much of the vehicles, clothes and other goods they carry. Officials have alleged truck owners may be behind some of the incidents, perhaps to claim insurance fraudulently.
On Sunday, Pakistan's ambassador to the U.S., Husain Haqqani, said the border crossing would be soon reopened.
Associated Press writers Rasool Dawer in Peshawer and Ashraf Khan in Karachi contributed to this report.