ISLAMABAD, Pakistan (CNN) -- A blast struck a crowd of Shia Muslims as they took part in a procession toward a mosque in central Pakistan Thursday evening, killing at least 24 people and wounding 50, according to police and emergency officials.
The explosion happened around 7 p.m. (9 a.m. ET) in the southern Punjab district of Dera Ghazi Khan, a rescue operator and district police said.
Officials said the blast was caused by an explosive device, but had no details on how the attack was carried out.
Video broadcast on Geo TV showed a chaotic scene as people tried to assist the wounded. Watch more about the blast »
As many as 600 people had gathered outside the Wadani Imam Bargah mosque to observe the 40th day of Muharram, a month of mourning for Shia Muslims, police said.
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