BAGHDAD - Twenty-one people were killed Wednesday in separate violent incidents in the Iraqi capital of Baghdad, including 13 bodies found in execution-style, police said.

Iraqi police found eight bodies in Arab Jubour area of southern Baghdad and five others in Shula district of the northwest, the source told Xinhua.

"The bodies were handcuffed and have bullet holes in their heads and chests," the source said.

Separately, gunmen broke into the house of a family in Baghdad' s northern district of Hurriyah and shot dead five family members, the source added.

In another incident, two people were killed and three wounded in a roadside bomb explosion at a crowded vegetable market in Doura district in the southern part of the capital, the source said.

Meanwhile, a roadside bomb ripped through the industrial area in Talbiyah district of northeastern Baghdad, killing a civilian and wounding four others, the source added.

Earlier in the day, police said that gunmen and suicide bombers attacked two police stations in and near the city of Ramadi, the capital of Iraq's western province of Anbar, killing at least seven policemen and wounding more than 20 others.

Iraq is witnessing its worst eruption of violence in recent years. According to the UN Assistance Mission for Iraq, almost 7, 000 Iraqis were killed and over 16,000 others injured from January to October this year.