At least 15 people were killed in violence around Iraq on Saturday, while authorities found the decapitated corpses of seven people dumped north of Baghdad in what appeared to be a sectarian revenge killing.

In central Baghdad, two bombs exploded in a parking lot in the Rasheed district shortly before 1:00 p.m., killing one person and injuring four others, police Lt. Bilal Ali said. The bombs, hidden in a pair of parked cars, set other cars and a nearby building aflame, Ali said.

CountryWatch: Iraq

One Iraqi soldier was killed and two injured when a roadside bomb struck an afternoon patrol in al-Rashad, about 37 miles southwest of the ethnically mixed northern city of Kirkuk. Iraqi forces rounded up 20 suspected militants following the attack, said a military spokesman, Col. Khelil Mohamed.

The decapitated bodies were found late Friday in an orchard in the city of Duluiyah, 45 miles north of Baghdad.

Three had been among a group of 17 construction workers kidnapped Thursday while traveling home to the predominantly Shiite town of Balad, police said. The corpses of the other 14 workers were found earlier Friday, also all beheaded.

The killings were apparently retaliation for the Wednesday kidnapping of three Sunni Arabs in Duluiyah by a Shiite militia based in Balad, police said. The three were killed and their bodies burned.

In Diwaniyah, 80 miles south of Baghdad, unidentified gunmen driving by in a car killed teacher Mohammed Muhsin al-Marmadhi as he was leaving his home, police Lt. Raed Jabr said.

A Shiite family of four were killed in Mahmoudiya, about 20 miles south of Baghdad, by unidentified assailants dressed in military-style uniforms who stormed into their house around dawn, army Capt. Oday Abdul-Ridha said.

Seven other people were killed in a mortar attack near Baqouba, 35 miles northeast of Baghdad, provincial police said. Five others were injured in the attack on the village of al-Rasoul.

In the western Yarmouk district of Baghdad, a delivery man was killed and another wounded when four armed men attacked their car, police Lt. Maitham Abdul Razzaq said.

Also in Baghdad, a journalist working for government-run TV was killed in a similar drive-by shooting in southern Baghdad on Friday night, police said.

Raed Qais al-Shammari, a technician with the al-Iraqiya station, had been standing near his home talking with a friend when he was shot by an unidentified gunman from a car in the violence-wracked Dora neighborhood, Razzaq said.

The attack follows the killings Thursday of 11 people at Baghdad's private Shaabiya television station. Shiite militiamen are suspected to have carried out that attack, possibly due to perceptions the newly formed station was backing their Sunni-Arab rivals.

The bodies of two unidentified men were also fished from the Tigris river in Suwayrah, 25 miles south of Baghdad. police Lt. Mohammed al-Shammari said.

The men had been blind folded with their hands and legs bound and were shot in the heads, al-Shammari said. Such bodies are found in the Tigris on a near daily basis, the suspected victims of sectarian death squads.