The 15-year-old was arrested on Monday at his home in the town of Amiriya, about 5 km south of Falluja, said an officer who participated in the arrest.

The arrest came a day before bombs ripped through apartment buildings and a market in mostly Shiite areas of Baghdad, killing some 50 people.

A preliminary investigation found that a neighbor had encouraged the boy to blow himself up near police, telling him he would "go to paradise,” to avenge the death of his father who was killed by security forces two years ago, the officer said.

"We acted promptly after receiving a tip and raided (the teenager's) house to find him sitting on a sofa with his body wrapped with an explosive vest," said the officer, who asked not to be identified. After interrogating the boy, police used an explosives sniffer dog to find the neighbor who had encouraged the boy.

"Using a sniffer dog, we managed to hold one woman suspect with explosives residue on her and we are waiting for final results of investigations to charge her," the officer said.

Hundreds of people are gathering for funerals in Tuesday's postelection bloodshed that threatens to rekindle sectarian violence that nearly destroyed the country three years ago.

Hundreds of men hoisting caskets and holding photos of loved ones walked through the streets of Baghdad, mourning the victims.

The attacks appeared to be an attempt by Al-Qaeda in Iraq or other extremists to exploit a power vacuum during what promises to be lengthy negotiations to form a new government.

About 120 people have been killed in and around the capital over the past five days - some of the most brutal strikes on civilians in months.