LAHORE, Pakistan (CNN) -- A suicide bomber killed at least 23 people and injured more than 58 others after detonating an explosive outside a court in Lahore on Thursday, police said. A rescuer helps an injured man following a suicide bomb attack in Lahore. The exact number of casualties varied, but state-run news agency the Associated Press of Pakistan said 22 police officers and one passerby were killed. Reports of another explosion triggered a dash toward a supposed second blast site, but those reports proved unfounded, said Aftab Cheema, senior superintendent of Lahore police. The suicide blast occurred in the city's commercial district, moments before lawyers were set to begin a rally outside the high court in the eastern Pakistani city to protest the rule of President Pervez Musharraf.
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NEW: Blast outside Lahore court kills at least 23 people and injures 58 others
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Suicide bomb exploded as lawyers were set to begin protest rally outside high court
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A man blew himself up after being stopped by police at a security barrier
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There were reports of a second blast, but these proved to be unfounded
Police said about 100 uniformed and plainclothes officers were at the scene ahead of the rally when the bomb went off about 11:45 a.m. @placeholder time (6:45 a.m. GMT).