(Adds detail of explosion) BEIRUT, May 20 (Reuters) - A woman was killed when an explosive device detonated near a shopping mall in eastern Beirut late on Sunday, a security source said. Witnesses said six people were wounded by glass when windows in the area of the blast shattered. "There was an explosive device either under a car or next to a car," another security source said, adding it took place in the car park of a popular mall in a Christian district in east Beirut. The first source said the woman was killed when a wall at her house collapsed on her. A Reuters witness said a plume of smoke could be seen rising from the area. Witnesses said the bomb appeared to have exploded under a car in a car park near the ABC department store, one of the biggest stores in Lebanon. The blast came as Lebanese troops battled Islamist militants based in a Palestinian refugee camp in the north of the country on Sunday and 48 people were killed in Lebanon's bloodiest internal fighting since the 1975-90 civil war.
