PETRINJA, Croatia—A strong earthquake hit central Croatia on Tuesday, destroying buildings and sending panicked people fleeing into rubble-covered streets in a town southeast of the capital. Authorities said at least six people were killed and dozens were injured. The European Mediterranean Seismological Center said the magnitude 6.3 quake hit 46 kilometers (28 miles) southeast of Zagreb. It caused widespread damage in the hardest-hit town of Petrinja. The same area was struck by a 5.2 quake on Monday. Officials said a 12-year-old girl died in Petrinja, a town of some 25,000 people. Another five people were killed in a nearly destroyed village close to the town, according to the state HRT television. At least 20 people were hospitalized, two with serious injuries, officials said, adding that many more people are unaccounted for. In Petrinja, cries could be heard from underneath destroyed houses. One woman was found alive some four hours after …