A total of six people were killed and 18 others injured Saturday in a series of attacks in Iraq's capital of Baghdad, local police source said.

Three roadside bombs exploded in the Hurria district of northwestern Baghdad in the evening, leaving four people killed and 15 injured, the source told Xinhua.

Xinhua reporters clearly heard two of three blasts in central Baghdad.

Later, a Katyosha rocket landed on a house in Obaede district of eastern Baghdad, killing one woman and wounding two civilians, said the source, adding their house was damaged.

In another attack, a man was killed and his wife was injured when a bomb exploded in their car in Al-Nissor square west of Baghdad.

Waves of violence and sporadic attacks continue in the Iraqi cities more than three months after the country held its landmark parliamentary election which is widely expected to shape the political landscape of the war-torn country.