Hilla: A car bomb exploded on Friday near a police station south of Baghdad where, a day earlier, a suicide attacker killed 24 policemen, a security official and an AFP journalist said.
No casualties were immediately reported as a result of the 2:00 pm (1100 GMT) explosion, just 50 metres (165 feet) from the bombing on Thursday morning that also wounded 72 people, a news agency reporter said.
A second explosives-packed vehicle was also found near the blast site in Hilla, 95 kilometres (60 miles) south of Baghdad, but security forces defused it, according to a police lieutenant.
Thursday`s bombing was the deadliest to hit Iraq in more than a month as security chiefs braced for revenge attacks by al Qaeda following the death of Osama bin Laden in a US commando raid in Pakistan on Sunday.
"Twenty-four policemen died, including five captains and two lieutenants, and 72 were wounded," said the director of Hilla`s main surgical hospital.
He added that, of the wounded, 25 remained in serious condition.
Thursday`s bombing left a two-metre (six-foot) crater and badly damaged the police station in the centre of the mainly Shiite city, capital of Babil province, in addition to several nearby houses and shops.
Hilla lies just beyond the edge of a confessionally mixed area south of the capital that earned the monicker Triangle of Death during sectarian bloodshed that peaked in Iraq in 2006 and 2007.
No group has yet claimed responsibility for the attack, but security forces nationwide began tightening security in the wake of the bombing.
Meanwhile, tribal chief Shahadha Hamad Ahmed was gunned down inside his son`s home in the main northern city of Mosul on Friday, police First Lieutenant Saud al-Badrani said.
Violence is down dramatically in Iraq from its peak, but attacks remain common. A total of 211 Iraqis were killed in violence in April, according to official figures.