Taliban Storm Pakistan Shiite Mosque, Killing at Least 20

Heavily armed militants stormed a Shiite mosque in Pakistan Friday, killing at least 20 people in an attack claimed by the Taliban as revenge for the execution of one of their cadres.

Three attackers with grenades, Kalashnikovs and explosive suicide vests struck at the Imamia mosque in Peshawar, the main city in Pakistan's restive northwest, around the time of the main Friday prayers.

The attack comes two weeks after a suicide bombing at a Shiite mosque in southern Pakistan killed 61 people, the deadliest sectarian incident to hit the country in nearly two years.

Nasir Durrani, the police chief of northwestern Khyber-Pakhtunkhwa province of which Peshawar is the capital, told Agence France-Presse that at least 20 people were killed and 45 others were wounded.

Durrani said that three attackers were also killed in the attack.

The Tehreek-e-Taliban Pakistan (TTP) claimed responsibility for the attack in an email statement, saying it was revenge for a militant known as Doctor Usman, who was hanged in December.

"This is a series of taking blood for blood, which will continue. The government should expect more and even harder responses," the statement said.

Police said the attack began when the militants entered from a nearby building site, cutting barbed wire to get into the mosque compound.

"One suicide bomber exploded himself in the verandah of the mosque while another was shot dead by police inside the main hall," Durrani said. 

"The third was caught by people but was also killed later on."

Eyewitness Mohammad Khalil told AFP a "huge explosion" shook the main hall of the mosque as prayers were coming to an end, and then the gunmen started firing on worshipers.

- Crackdown on militants -

TV footage in the immediate aftermath showed people running away from the scene, some carrying injured on their shoulders, others limping, as police fired shots and checked people at a barrier.

The mosque is close to several government buildings including the offices of the Federal Investigation Agency and passport agency.

Since June last year the army has been waging a major campaign against strongholds of TTP and other militants in the North Waziristan tribal area, which lies close to Peshawar.

The military has heralded the success of the operation, which it says has killed more than 2,000 militants, though the precise number and identity of those killed cannot be verified independently.

The country has stepped up its fight against militants since Taliban gunmen massacred more than 150 people, most of them children, at a school in Peshawar in December.

On Thursday the military said it had taken 12 Taliban members into custody over the school attack, including the imam of a mosque.

Following the massacre, Prime Minister Nawaz Sharif ended a six-year moratorium on the death penalty and Doctor Usman, also known as Aqil, was one of the first to go to the gallows.

He was convicted for an attack on the army headquarters in Rawalpindi in 2009 and was arrested after being injured.

Sectarian violence has been on the rise in Pakistan in recent years, most of it perpetrated by hardline Sunni Muslim groups against minority Shiite Muslims, who make up around a fifth of the population.

The suicide bombing at a mosque in southern Sindh province on January 30 was the deadliest sectarian attack in Pakistan since February 2013, when 89 were killed in a market bombing in the southwestern city of Quetta.

Anti-Shiite attacks have been increasing in recent years in Karachi, Quetta, the northwestern area of Parachinar and the far-northeastern town of Gilgit.