LAHORE, Pakistan (CNN) — Gunmen opened fire Tuesday on a procession of Shiite Muslim worshippers in the southwest Pakistani city of Quetta, killing at least 38 people and wounding more than 100, government officials said.
The procession of hundreds, including women and children, was part of a celebration marking Ashura, the 10th day of the holy month of Muharram. The shootings triggered a stampede, although there was no word of deaths resulting from the stampede.
There were also reports of more gunfire in the city after the attack. Quetta’s mayor imposed a curfew. Maj. Gen. Shaukat Sultan, a Pakistani military spokesman, said army and paramilitary troops have been called in to provide additional security.
No arrests were made and police said a search for the unknown number of gunmen was under way.
Sectarian violence between extremist Sunni and Shiite groups has been responsible for many deaths in Pakistan.
Also Tuesday, a local Shiite leader was shot and killed in Mundi Bahauddin, about 100 kilometers (62 miles) northwest of Lahore. Individual sectarian killings are common in Pakistan.
The attacks in Pakistan came on the same day that a series of deadly explosions killed many Shiite worshippers in Iraq. Those attacks were in Baghdad and the Shiite holy city of Karbala.
There was no immediate evidence the attacks in Pakistan and Iraq were connected.
Quetta was the site of one of the worst acts of sectarian violence in years in Pakistan when armed militants stormed a Shiite mosque last July, killing more than 50 people. The attackers tossed grenades and shot at worshippers during Friday prayers.
Authorities said they believed a Sunni extremist group may have been behind that attack.
Many Sunnis and Shiites live peacefully together in Pakistan. Sunnis outnumber Shiites by a ratio of about four-to-one. Muslims make up 97 percent of Pakistan’s population.
Security had been stepped up nationwide in Pakistan for Muharram, the first month of the Islamic year.
Ashura is the holiest day for Shiites and commemorates the seventh century death of Imam Hussein — a top Shiite saint and the grandson of the prophet Muhammad — who died in 680.