The Pakistani Taliban have issued their first videotaped message since Osama bin Laden was killed by US Navy Seals earlier this month.

In the exclusive footage, obtained by Kamal Hyder, Al Jazeera's correspondent in Islamabad, the group is shown vowing revenge for the al-Qaeda leader's death.

The message, from a man called Umar Khalid, said the group would "take revenge" for Osama's killing, saying that Pakistan and the US's intelligence agencies were now on its "hit list".

He added that bin Laden's influence was still strong despite his death.

"Osama bin Laden has given us the ideology of Islam and Jihad ... by his death we are not scattered ... but it has given us more strength to continue his mission," he said.

"It took the Americans 11 years to kill Osama but for us it is easy, we will take our revenge in less than a few months."

Khalid and his men are now hiding in the mountains, and appear to be well-armed with assault rifles and other weapons. They are also shown with a laptop and a radio.

The group use motorcycles and a station wagon, camouflaged under several inches of mud, to move around.

Meanwhile on Wednesday, dozens of fighters attacked security checkpoint in northwestern Pakistan, killing two policemen and wounding several others.

Up to 100 fighters reportedly stormed the post near the Khyber tribal area, a stronghold for Taliban fighters.

The Taliban have staged a number of attacks in Pakistan since bin Laden was killed in a US raid on May 2 near the Pakistani capital Islamabad.

Last Friday, at least 76 people were killed in a double suicide bombing on a Frontier Constabulary training centre in the northwestern town of Charsadda.

The Pakistani Taliban said they carried out the attack - this year's deadliest on the security forces - to avenge bin Laden's death in a compound in the Pakistani town of Abbottabad.

Al-Qaeda's interim leader

In another development on Wednesday, Al Jazeera learned that al-Qaeda has appointed a temporary leader and a new head of operations.

Saif al-Adel, an Egyptian, was named interim leader, while Mustafa al-Yemeni, would direct operations.

US prosecutors say Adel is one of al-Qaeda's leading military commanders and helped plan the bomb attacks against the American embassies in Nairobi and Dar es Salaam in 1998.

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They also say he set up al-Qaeda training camps in Sudan and Afghanistan in the 1990s.

An al-Qaeda expert had said on Tuesday that Adel would likely not act as head of the organisation.

"This role that he has assumed is not as overall leader, but he is in charge in operational and military terms," Noman Benotman, a former bin Laden associate who is now an analyst with Britain's Quilliam Foundation think tank, said.

Adel was believed to have fled to Iran after the US invasion of Afghanistan following the September 11, 2001 attacks on the United States, and was subsequently held under a form of house arrest there, according to some media reports.

Arab media reports said Iranian authorities released him from custody about a year ago, and he then moved back to the Afghanistan-Pakistan border region. Some analysts say Adel may have returned to Iran or Afghanistan in recent weeks.

Source: Al Jazeera and agencies