Ibrahim Bajilan, the provincial council chief, said the attack was intended to be a double suicide bombing, but a man accompanying the first bomber failed to detonate his explosives vest and was arrested at the scene.

"We were inside the court building when we heard a thunderous explosion
followed by people's cries," Abu Mohammed, a 55-year-old lawyer in the
courthouse at the time, said.

"We rushed outside the building. We couldn't see anything because smoke was everywhere."

One resident said the target appeared to be Iraqi military vehicles parked outside the courthouse, and that five shops in front of the courthouse were damaged.

Baquba and surrounding areas have been struck by several female bombers
in recent months despite US efforts to recruit and train more women for the
Iraqi security forces.

The military has warned that women have been increasingly used as attackers because they are less likely to be searched and due to the clothing they often adopt - the abaya - a long, black robe, which can hide explosives.

Local authorities have deployed more than 50 women in the area to search for possible female bombers, but more were needed to control the roads leading to the city, officials said.

Security control

Iraq's government said on Wednesday it was ready to take over security responsibilities from US security forces in Baghdad as both countries say they are nearing a deal on their controversial military pact.

Major-General Abdel Karim Khalaf, the interior ministry spokesman, said Iraqi police are capable of handling security duties across the capital, a responsibility now held by US troops.

A medical official said six security personnel were killed in the attack [AFP]
"We have the ability to take over the internal security responsibility in Baghdad if American forces pull out of the city," he said in a statement.

"The interior ministry is able to take responsibility for protecting Baghdad."

His remarks came a day after Hoshyar Zebari, the foreign minister, said Washington and Baghdad are now "very close" to an agreement on the presence of American troops in the country beyond 2008.

"There have been new ideas and new language that could be acceptable, but no final decision has been made. This needs some bold political decisions now," Zebari said on Tuesday.

Zebari was speaking at a news conference with John Negroponte, the visiting US deputy secretary of state, shortly after two bombs went off just outside the Green Zone, leaving at least seven people, including an Iraqi soldier, injured.

Iraqi authorities have also unveiled a new hotline to protect journalists in the country, which they say has saved the lives of two journalists since it opened last week.