Suspected rebels from Uganda's Lord's Resistance Army (LRA) shot dead two local aid workers in the remote north of the country on Wednesday, a United Nations security official in the region said. The LRA has seldom targeted humanitarian staff in the past, but in two days there have been three attacks on three different aid agency vehicles in three neighbouring districts. "A Caritas staff member named Joseph Stalin was shot dead today in Kitgum district. He was a passenger on a motorbike that was fired on," the U.N. security official told Reuters. "Then, later this afternoon a clearly marked Accord vehicle was shot at in Pader district. One man, a local staff member, was killed and two others were critically injured." On Tuesday, two local aid workers were shot and wounded when their Christian Children's Fund car was ambushed by suspected LRA rebels, aid workers in the region said. The two men were flown by helicopter to a Kampala hospital. "It is clear that the aid community is now being targeted," a senior aid worker in the capital told Reuters.