MOGADISHU  - Ethiopian forces opened fire on two civilian buses near the Somali capital Mogadishu on Friday, killing at least 30 passengers, witnesses told AFP. Ethiopian soldiers in the town of Arbiska sprayed gunfire on the two vehicles, one of which was travelling from the capital and the other from nearby Afgoye, the witnesses said. "I saw 37 dead civilians near Arbiska, where the Ethiopian forces indiscriminately opened fire on two civilian buses," said Ahmed Husein Mohamed, a local elder who witnessed the killings. All the witnesses and local residents contacted by AFP gave death tolls of at least 30. They said all the victims appeared to be civilians and described scenes of carnage. "It's a scene of complete destruction of human life, everyone is dazed," Mohamed said. "They killed everyone on the buses, there was blood everywhere. It was unbearable to look at the scene," said witness Amino Hasan Adan. She said she personally counted the bodies of 29 men, seven women and a child. It was not immediately clear what prompted the Ethiopian troops - in Somalia to prop up a fragile government under attack from Islamist forces - to open fire. The Ethiopians had come under attack three times earlier Friday, once by a roadside bomb and twice by gunfire from Muslim fighters. "The Ethiopian forces opened fire on the two civilian buses and they killed many. I personally counted 15 just in one spot but I could not reach some of the other places, where people are saying many others were killed," said Adan Moalim Yahye, another witness. Hassan Sheikh Ali, a medic at the nearby Afgoye hospital, said 10 wounded were brought in following the incident. "Most of them are in shock but they explained that many civilians were indiscriminately killed," he told AFP. The bloodshed in Arbiska came only two days after a similar incident south of Mogadishu, on the road between the capital and the town of Wanlaweyn. According to witnesses, Ethiopian forces mistook a civilian minibus travelling at night as hostile and opened fire, killing five civilians.