A passenger train traveling from Athens to the northern city of Thessaloniki derailed in central Greece on Saturday, injuring 23 people, authorities said. The Greek railway company, OSE, said the InterCity train derailed about 440 kilometers (270 miles) north of the capital for reasons that were unclear. Twenty adults and three children were taken to a nearby hospital. Most were treated and released, but 11 of the injured remained in the hospital by early afternoon for observation, OSE said. It did not specify whether the three children were among the 11.