The PUK chief in Mosul, Saad Pira, told AFP that 17 people were killed and more than 40 wounded when a suicide car bomber rammed their convoy at around 4:30 p.m. as they were travelling through the Karama neighbourhood of Mosul.
"An Opel car slammed into the convoy and exploded against the minibuses, two of which were totally gutted by fire," he said. The attack took place near the PUK headquarters in Karama.
In Baghdad, at least four policemen were killed and 49 others wounded in a double car bombing, medics said, one day after 26 people were killed in twin attacks claimed by militants loyal to Iraq's most-wanted man, Abu Musab al-Zarqawi.
Two cars were detonated simultaneously, ripping through the Salhiyah police station just outside the main entrance to the heavily fortified "Green Zone" - home to Iraqi government offices and foreign embassies, the US military said.
The facade of the station was blown off. Around 10 civilian cars were strewn, gutted in the street, while another was blown onto the roof of a neighbouring two-storey building by the force of the blasts.
Meanwhile, four multinational soldiers have been killed since late Friday, the US military said. Two US soldiers were killed in separate roadside bomb attacks in Baghdad and the rebel hotspot of Baquba.
Two multinational force soldiers were killed and five wounded in a car bombing at the Trebil border crossing between Jordan and Iraq late Friday, which has forced the closure of the border.
Meanwhile, at least 13 others were reported killed or their bodies found on Saturday from a string of attacks across the country - including two men mown down in broad daylight in Baghdad.
Three people were killed in the oil-rich region of Kirkuk, while a former intelligence officer under Saddam, Zaid Hassan, was assassinated by masked gunmen in Baquba.
Back in Mosul, nine more bodies of security officers were discovered, bringing to 66 the number of police or national guardsmen who have been found dead in the city since November 19.
The body of woman official from Saddam's home province of Salaheddin, who was kidnapped on Thursday, was found near the oil refinery town of Baiji.
Meanwhile, 850 British soldiers sent to back up US forces in an anti-insurgent operation south of Baghdad returned to their base in the southern city of Basra, London's defence ministry announced.
Three suspected Iraqi members of the Ansar al-Islam group, were brought before a German magistrate on suspicion of plotting an attack against visiting Iraqi Prime Minister Iyad Allawi, on a European tour.