Explosion injures 4 people in downtown Beirut At least one grenade exploded at a downtown Beirut square early Sunday, injuring four people, police said. Police and army troops ringed the area and an investigation was under way. The attackers struck around 2:30 a.m. Sunday (Israel time) and fled. Some witnesses said more than one grenade was launched but that could not be confirmed. It could not be immediately determined who was behind the attack and whether it was politically motivated. The prime minister's office is about 100 meters away overlooking the square and the Parliament building is on another square a few buildings behind Riad Solh.