WASHINGTON — A subway train derailed Sunday near downtown Washington, sending 20 people to the hospital and prompting the rescue of 60 people from a tunnel, officials said.The accident happened at about 3:45 p.m. near the underground Mount Vernon Square station, which serves two lines beneath the Washington Convention Center, Metro spokeswoman Cathy Asato said. There were about 150 people on the train.For more details, follow the link below.