Updated

Police said Monday they were questioning two men in connection with a suicide attack at a Shiite mosque in eastern Pakistan (search) that killed three people plus the bomber — the latest violence in what appears to be rising strife between Shiite and Sunni Muslims (search).

Two security guards died in the attack Sunday while confronting the bomber and preventing far more deaths by blocking his entrance into Husainia Hall mosque (search) in Lahore during evening prayers. The bomber and a passerby also were killed and eight were wounded, Punjab province Law Minister Raja Basharat Illahi said.

Seventy to 80 people were in the mosque for prayers when a man carrying a briefcase tried to enter but was blocked by the guards, officials said. A bomb in the briefcase exploded after a scuffle, during which one of the guards opened fire.

Two men were picked up in the neighborhood where the mosque is located shortly after the bombing, a senior police official in Lahore said on condition of anonymity.

The men — who have not been formally arrested — looked suspicious and tried to run away when police confronted them, he said. Their identities were not given.

The bombing in Lahore came the same day that thousands of people mourned two Sunni Muslim clerics who were gunned down in the southern city of Karachi a day earlier.

The bomb attack was the third this month against a religious target in Punjab in apparent sectarian violence between Shiite and Sunni Muslims.

On Oct. 1, a suicide bombing at a Shiite mosque killed 31 people in Sialkot city. Six days later, a car bombing at a gathering of Sunni radicals in Multan city killed 40.

No group claimed responsibility for those attacks, which prompted authorities to ban religious gatherings nationwide except for Friday prayers at mosques.

Meanwhile, police and intelligence agents detained about 70 additional people with alleged links to banned extremist groups during raids late Sunday night in Multan and several nearby towns, an intelligence official based in Multan said Monday on condition of anonymity.

Forty of the arrests were made in Multan, he said.

On Sunday, more than 125 militants had been detained for questioning in connection with the Sialkot and Multan bombings and as part of efforts to stop more sectarian violence.

On Saturday, two prominent Sunni clerics, Mufti Jamil and Nazir Ahmed Taunsvi, were gunned down in the volatile city of Karachi, triggering nighttime riots by their followers who set fire to at least four vehicles.

About 10,000 mourners gathered on Sunday at a downtown Islamic seminary, where funeral prayers for Jamil were held amid tight security, with police sharpshooters on rooftops and riot police outside gas stations and banks.

Jamil was known as a pro-Taliban scholar. He was part of a delegation that traveled to Afghanistan after the Sept. 11, 2001, attacks to try to persuade Taliban leaders to hand over Osama bin Laden.

The spate of attacks in Pakistan over the past 10 days comes despite scores of arrests of terror suspects in recent months, and the Sept. 26 killing by security forces of key al-Qaida suspect Amjad Hussain Farooqi — accused in the 2002 beheading of American journalist Daniel Pearl.