BAGHDAD — Three members of the same family and two other people were killed in violence in the capital and northern Iraq on Sunday, including a string of Baghdad rocket attacks, a security official said.

In the deadliest incident, gunmen wearing police uniforms stormed a family home in the Bayaa district of southwest Baghdad and killed three people, an interior ministry official said, without giving a motive.

He said another person was killed and 12 wounded in nine rocket attacks across Baghdad, including five fired into the heavily-fortified Green Zone that is home to the US embassy and parliament.

Baghdad operations command, which is responsible for security in the capital, said security forces had seized a rocket launcher in Al-Nahdha district, close to the interior ministry.

Eleven rockets were also seized, it said, without any arrests made.

A roadside bomb near the National Theatre in central Baghdad, meanwhile, wounded three people, the security official added.

And in Tikrit, north of Baghdad, a sticky bomb affixed to a car carrying three tax agency officials exploded, killing one of them and wounding the two others, a police officer in the city said.

Violence in Iraq is down from its peak in 2006 and 2007 but attacks remain common, especially in Baghdad. A total of 211 people died as a result of attacks in April, according to official figures.