TWO people were killed and two injured when suspected Unita rebels ambushed their vehicles as they were carrying out a polio vaccination campaign in Angola, officials said on Monday. The health ministry initially said one person died in Saturday’s attack near Calomboloca, 80km southeast of Luanda. It was blamed on Unita rebels, who made off with various supplies and vaccines. The two injured people were hospitalised in Luanda. Meanwhile, at least three people, two of them government troops, were killed in an ambush Saturday in the northern Cabinda province, near the border with Congo, according to Radio Ecclesia, a Roman Catholic station.