In video footage released by Iraqi police, a teenage girl with an explosives vest tightly strapped to her body is seen handcuffed to a metal grid, her head repeatedly falling forward as several policemen huddle around her.

After several minutes, the officers lift her flowered robe, remove the white vest hidden underneath and then take her for questioning, videotaping her in the presence of reporters. They prod her to confess to plans to stage a suicide attack, but she denies the allegation.

The arrest of the girl, who gave her first name as Rania, heightened concern about a rise in suicide bombings by women in Iraq. The number of female bombers has more than tripled, from eight in 2007 to 29 this year, according to U.S. military officials.