BY REBECCA BENNETT — Metro said its fourth new set of 7000-series cars entered service on Monday, Aug. 17.  The new train departed Greenbelt at 5:30 a.m. and is now assigned to the Green Line, a press release said.

The transit authority said the new 7000-series rail cars first debuted in April and are currently running one each on the Red, Orange and Blue lines.  A total of 748 new cars have been ordered, but Metro said 52 have been delivered to date.