Pakistani police say gunmen have killed four Shi'ite Muslims in a suspected sectarian attack in the country's northwest.

The shooting marks the second day of deadly violence in North West Frontier Province.

Authorities say at least three of the victims in Tuesday's attack in the town of Hangu were members of the same family.

On Monday, a bomb exploded at a Shi'ite mosque in the same province, killing four people and wounding at least three others. The bomb went off as worshipers were leaving the mosque in Dera Ismail Khan after evening prayers.

No one has claimed responsibility for either attack.

Pakistan's majority Sunni and minority Shi'ite communities generally coexist peacefully, but militants from both sides have attacked each other since the 1980s.

Pakistan's new coalition government is trying to negotiate an end to the militant violence. Despite the effort, attacks continue to take place.

A top Interior Ministry official told parliament today that authorities prevented suicide attacks on a protest by lawyers in Lahore last week. He said authorities arrested six suspected bombers and seized 45 kilograms of explosives.

Lawyers and activists held the march to urge the government to restore judges fired by President Pervez Musharraf under emergency rule last year.

Some information for this report provided by AP, AFP  and Reuters.