A bomb has exploded in Baghdad, causing a huge ball of fire that engulfed a minibus carrying several passengers. Police said a roadside bomb placed near a fuel truck caused the explosion that killed 17 Iraqis and wounded several more. Aljazeera's correspondent said the bomb went off in the Bayya district around 08:30 local time on Wednesday morning. Meanwhile, US troops are scouring a region north of Baghdad for resistance fighters and have raided homes in the town of Samarra, arresting 73 suspects on Tuesday night. The 4th Infantry Division, based in Tikrit, confirmed the arrests, and said latest searches were part of Operation Ivy Blizzard. **More foreign troops*** South Korea's government ended months of divisive debate on Wednesday by announcing its final decision to send a contingent of 3000 troops to Iraq. The decision endorsed at a cabinet-level security meeting chaired by President Roh Moo-Hyun provides for the deployment of combat and non-combat troops, the president's office said. However, the contingent will not ensure the security of the region in which it is deployed, National Security Adviser Ra Jong-yil said. The South Korean contingent will take on responsibility for support of Iraqi peace and rehabilitation, and will independently take charge of a certain region," he said. "The Iraqi military and police will be in charge of security in that region." The decision must be endorsed by parliament and a motion will be sent to the National Assembly next week, Ra said. **Non combatant assistance*** Japan, committed to sending military personnel to Iraq but cautious about their safety, is planning to send its first substantial contingent of 135 ground troops there on 21 February, a national daily said on Wednesday. Quoting a defence ministry proposal, the Mainichi Shimbun said Japan would first send an advance party of 28 troops on 14 January to begin preparations, followed by a 78-strong logistics team on 31 January. The 135 troops will then leave, and a total of about 550 troops will be in place by the end of March, according to a ministry proposal which the paper said had been presented to the ruling coalition. **PHOTO CAPTION*** An Iraqi policeman inspects the wreckage of a minibus after an explosion in Baghdad December 17, 2003. (REUTERS/Akram Saleh)