Lahore, PAKISTAN (Agencies)

Pakistan's second city Lahore was on high alert Friday after three suicide bombers blew themselves up in an Islamic shrine packed with worshippers, killing 41 people and wounding scores more.

Hundreds of devotees were visiting the marble shrine of the 11th century Persian Sufi saint, Syed Ali Hajwairi, commonly known as Data Gunj Bakhsh, in the heart of the city when the attacks occurred.

Muslims in Pakistan visit shrines and mosques in large numbers on Thursday nights and Friday.

"Dead bodies are scattered all over the courtyard of the shrine," Reuters photographer Mohsin Raza said from the scene. "There is blood everywhere. Two of the dead were my friends. It's very horrifying," he said in a choked voice.

One of the attackers blew himself up at the gate of the sprawling, marble shrine while two other attacks took place in the basement of the shrine where people were washing for prayers.

Sajjad Bhutta, a top city administrator, said at least 41 people were killed and 122 wounded.

	It was all chaos. People were screaming for help and running here and there. It was all smoke. Nothing could be seen and only cries could be heard
Witness Mian Rauf

Chaos

Mian Rauf, a witness, said devotees were settling down inside the mausoleum and the courtyard for final prayers when the attacks happened.

"First there were three small blasts. People got panicky and started running. But within moments there were big explosions," he said.

"It was all chaos. People were screaming for help and running here and there. It was all smoke. Nothing could be seen and only cries could be heard."

Taliban militants generally abhor the Sufi strand of Islam and disapprove of visiting shrines, which is popular with many Pakistanis.

Attack on USAID

Meanwhile, Six suicide bombers stormed a USAID compound in northern Afghanistan before dawn Friday, killing at least four people and wounding several others, officials said. At least two of the dead were foreigners.

The brazen attack came on the same day that Gen. David Petraeus landed in the Afghan capital to take command of U.S. and international forces fighting the nearly 9-year-old war. Petraeus arrived from Brussels where he sought to reassure allies that the war against the Taliban was on track despite rising casualties and problems regaining control over key parts of the country.

The Taliban claimed responsibility for the attack, which began about 3:30 a.m. in Kunduz when a suicide car bomber blew a hole in the wall around a building used by Development Alternatives Inc., a Washington, D.C.-based global consulting company on contract with the U.S. Agency for International Development, or USAID. The company is working on governance and community development in the area.