Suicide bombers² have launched a deadly attack on a Sufi shrine³ in the eastern Pakistani city of Lahore.

巴基斯坦东部城市拉合尔一座苏菲派神殿遭遇自杀式炸弹袭击。

At least 37 people died in the blasts（爆炸） at the popular Data Darbar shrine late on Thursday evening, officials say.

At least 175 other people were hurt in the blasts, believed to be the first targeting a shrine in Lahore.

Thousands of people were visiting the shrine at the time, officials say. It holds the remains⁴ of a Persian Sufi saint, Abul Hassan Ali Hajvery.

The shrine is visited by hundreds of thousands of people each year from both Sunni（逊尼派教徒） and Shia（什叶派） traditions of Islam.

At least two attackers were involved, although police initially⁵ said three explosions had been heard.

The impact of the blasts ripped open the courtyard of the shrine. Rescue workers could be seen clambering（攀登） over the rubble⁶ as they carried out the victims.

Khusro Pervez, commissioner⁷ of Lahore, said two of the attacks took place in the main courtyard and one in the lower level of the shrine.

The first attacker struck in the underground area where visitors sleep and prepare themselves for prayer, he said. As people fled, a second bomber¹ detonated（引爆，爆炸） his explosives in the upstairs area.

Officials say they believe the bombers used devices packed with ball-bearings to maximise the impact of their attack.

A volunteer security guard at the shrine described scenes of devastation⁸（毁坏，荒废） .

"It was a horrible scene," said Mohammed Nasir. "There were dead bodies all around with blood and people were crying."

The attack is the biggest on a Sufi shrine in Pakistan since militant⁹ attacks began in 2001.

No group has said it carried out the attack, but correspondents say the attacks continue a growing trend among militants¹⁰ to target members of other sects¹² as well as minorities.

History of attacks

Lahore has been hit by a series of bomb attacks, including a suicide blast at anti-terrorist offices in March, when at least 13 people died.

In May, more than 90 people were killed in a double attack on the minority Ahmadi sect¹¹ in the city.

Earlier, security chiefs had been congratulating themselves after what was the first month in two years in which there had been no suicide bombings in Pakistan, the BBC's Aleem Maqbool reports from Islamabad.

They said it was proof the militant networks had been disrupted. Most Pakistanis knew the battle against militancy¹³ in this country was far from over, he adds.

Last year Pakistan launched a major military offensive against militant strongholds（据点，要塞） in South Waziristan.

In December the military said they had achieved victory, but subsequent reports have suggested the militants remain active in the region.