A suspected suicide car bombing at a Roman Catholic church in the restive central Nigerian city of Jos has caused a number of casualties, officials say.The car was apparently stopped before it could enter the church compound, one report said.No group has said it carried out the attack.A bombing at a Jos church two weeks ago killed three people and injured nearly 40. Islamist militants from Boko Haram said they carried out that attack.Emergency officials were assisting the victims at St Finbar's church in the Rayfield area, a spokesman for the national emergencies agency said."The blast killed the bomber and injured three other people who are lying unconscious on the ground," Yushau Shuaib told AFP news agency."The bomb exploded before he could get to the church," he said.Another report suggested that at least three people were killed in addition to the bomber.A Reuters reporter at the scene said police had cordoned off the area around the church.