A psychiatric hospital official has been detained in Baghdad in connection with bombings by two allegedly mentally disabled women, says the US military.
The blasts tore through two popular animal markets
The man is suspected of supplying patient information to al-Qaeda in Iraq, spokesman Rear Admiral Gregory Smith told a news conference.
Twin bombings of crowded pet markets on 1 February killed at least 98 people.
Officials later said the explosives had been attached to two mentally disabled women and were remotely detonated.
Rear Adm Smith identified the suspect, who was detained on Sunday, as an acting administrator at Rashad hospital in the capital.
The detainee is said to work in Rashad psychiatric hospital
"Coalition forces detained a hospital administrator in connection with the possible exploitation of mentally impaired women by al-Qaeda," he said.
"The administrator remains in coalition force detention and is being questioned to determine what role if any [he played] in supplying al-Qaeda with information regarding patients at the al-Rashad psychiatric hospital or from other medical facilities in Baghdad," he added.
US troops had carried out a "thorough" search of the hospital, he said.
The toll of the twin attacks on 1 February was the highest seen for months in Baghdad, where a fragile sense of security had begun to emerge as the bloodshed apparently diminished.
US and Iraqi officials blamed the bombings on al-Qaeda, saying they were a reflection of its "twisted" ideology.