Three American soldiers have been killed and another has been wounded after a roadside bomb exploded near their patrol in Baghdad, the US military announced on Tuesday.
In a statement, the military said the incident took place in southeastern Baghdad.
The latest deaths bring to around 40 the number of US soldiers killed in Iraq this month, putting April on course to be one of the deadliest months for US soldiers in some time.
More than 3,280 American soldiers have been killed in Iraq since the 2003 invasion.
Iraqi police said on Tuesday that a female suicide bomber had detonated her explosives among police recruits northeast of Baghdad, killing at least 10 people.
In central Baghdad, clashes erupted between US forces and fighters and an American helicopter came under ground fire but was not brought down, US and Iraqi officials said on Tuesday.
The fighting raged in Fadhil and Sheik Omar, two Sunni-dominated neighbourhoods of the Iraqi capital, two Iraqi police officials said.
They spoke on condition of anonymity because they were not authorised to speak to the media.
Four civilians were injured in the clashes, police and a hospital official said, on the same condition of anonymity.
A US helicopter hovering over the battle "received some ground fire, but was not brought down", according to a senior US military official.
He spoke on condition of anonymity because US officials were still investigating the incident.
Güncelleme Tarihi: 20 Eylül 2018, 18:16