More than 20 people were killed and around 50 injured in three separate bombings that hit Baghdad on Monday, police and medical personnel said.
Twelve people were killed and more than 20 injured when a car bomb blew up in the northern Shaab Shi'ite district.
Eight were killed and 21 wounded by a suicide bomber who detonated a car near a government building and a police station in the district of Tarmiya.
A third bomb involving a suicide bomber on a motorcycle in Sadr City killed three people and injured nine.
The attacks came as Iraqi forces and Shi'ite militias fought so-called Islamic State militants in Falluja, around 66 km west of the capital.
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The incident is not believed to be terror-related, British Transport Police said.
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A small number of people were treated at Southgate Tube station, British Transport Police said.