Q+A: Who are the Pakistani Taliban insurgents?

(Reuters) - Militants have conducted eight bomb attacks in Pakistani towns and cities since late April, when the army began an operation to root out Pakistani Taliban from their stronghold in the Swat region.

The Taliban claimed responsibility for a suicide gun and bomb attack in the eastern city of Lahore on Wednesday in which 24 people were killed, saying it was revenge for Swat and vowing more violence.

Here are some questions and answers about the Pakistani Taliban:

WHO ARE THE PAKISTANI TALIBAN?

Most Pakistani Taliban fighters are ethnic Pashtuns from northwestern regions on the Afghan border. They support the Afghan Taliban, most of whom are also Pashtun and many of whom fled to the Pakistani Pashtun lands after U.S.-led forces ousted Afghanistan's hardline Taliban government in late 2001.

Thirteen factions based in different parts of northwest Pakistan have formed a loose umbrella group, the Tehrik-e-Taliban Pakistan (TTP), or Taliban Movement of Pakistan, led by Baitullah Mehsud, based in South Waziristan on the Afghan border.

The United States in March announced a reward of $5 million for information leading to Mehsud's location or arrest.

Mehsud has been accused of being behind a wave of suicide attacks across Pakistan since the army stormed Islamabad's Red Mosque in July 2007 to crush a militant movement based there.

But it was when the government named Mehsud as the chief suspect in the assassination of former Prime Minister Benazir Bhutto in 2007 that Mehsud's notoriety rocketed.