Updated at 11:40 p.m.

A train carrying hundreds of passengers lost power inside a Metro tunnel Tuesday evening and was stuck for more than an hour before rescuers got them out, Metro officials said.

More than 250 people were on the Green Line train, fire department spokesman Tim Wilson said. Metro spokesman Dan Stessel said it appeared that no one was injured in the incident, near the Georgia Avenue-Petworth station in the District, though a woman was seen on a stretcher outside the station.

The third rail, which powers the trains, lost electricity shortly before 6 p.m., but hours later it was still unclear why it happened, said Metro spokeswoman Morgan Dye. She added that everyone had to be removed from the train before Metro could investigate the problem.

At about 11 p.m., train service on the Green and Yellow lines was fully restored, according to a tweet from Metro officials, and the Columbia Heights and Georgia Avenue stations were reopened.

Stessel said fire and emergency medical personnel evaluated every passenger on the train to see whether anyone needed medical attention. Once the passengers were off the train, they were transferred to several buses outside the station.

Riders on the northbound Green Line train said it came to a sudden stop in the tunnel, about 100 feet from the platform at the Georgia Avenue station. The train’s lights and air conditioning went out, and the conductor announced that the train had lost power.

“There was no smoke. It was hot, but for the most part, people were okay,” said Boubacar Hanes, who was on the train.

Passengers said a few people did not wait for rescuers; they walked out through the tunnel on their own.

Lauren Kiesler, who lives in the Adams Morgan neighborhood, said she was heading to visit a friend in College Park. Children were crying, and a pregnant woman had to go to the bathroom, she said.

Earlier, service between U Street and Fort Totten, a busy portion of the Green and Yellow lines, was suspended because of the power problem.

Updated at 9:20 p.m.

A train carrying at least 500 passengers was stopped in a Metro tunnel for more than an hour Tuesday evening before rescuers got them out, Metro Transit Police said.

Metro spokesman Dan Stessel said it appeared that no one was injured in the incident near the Georgia Avenue-Petworth station, and the cause of the power failure had not been determined as of about 8 p.m.

Earlier Tuesday evening, Stessel said fire department personnel  were evaluating every passenger on the train to see if anyone needed medical attention.

Once the passengers were off the train, they were transferred to several buses outside the station. station.

Riders on the northbound Green Line train said the train came to a sudden stop in the tunnel,which was about 100 feet from the Georgia-Avenue Petworth station, around 6:10 p.m. The train’s lights and air conditioning went out and the conductor told them the train had lost power.

“There was no smoke. It was hot, but for the most part people were okay,” said Boubacar Hanes, who was on the train.

Passengers said a few passengers did not wait for rescuers — they self-evacuated and walked through the tunnel.

Lauren Kiesler, who lives in Adams Morgan, said she was heading to visit a friend in College Park. Children were crying and a pregnant woman had to go to the bathroom, she said.

Service was suspended on a busy portion of the Green and Yellow lines because of the power problem. As of 8 p.m., Green Line remained suspended between U Street and  Fort Totten, a Metro alert said.

“There has been no attempt to restore power,” Stessel said in an e-mail.

Green Line trains remained suspended between U Street and Fort Totten , a Metro alert said. Yellow Line trains begin and end at Mt. Vernon Square.

Johnathan O’Connell contributed to this report.

Updated at 7:52 p.m.

A train carrying passengers was stopped in a Metro tunnel for more than an hour Tuesday evening before rescuers got them out, Metro Transit Police said.

Metro has suspended service on a busy portion of the Green and Yellow lines due to a power problem. The transit police tweeted at about 7:30 p.m. that an orderly evacuation of passengers had begun.

Trains were not running from U Street to Fort Totten.

Spokesman Dan Stessel said that firefighters are on board the train stuck in the tunnel, which is about 100 feet past the Georgia Avenue/Petworth station. Earlier Tuesday evening, he said fire department personnel  were evaluating every passenger on the train to see if anyone needed medical attention.

At that point, they would start bringing all the passengers up from the tunnel, Stessel said.

Stessel said that the train did not have power, but there was no smoke in the tunnel.

Metro said that the power problem started at Georgia Avenue. That means that no trains will service U Street, Columbia Heights, Georgia Avenue/Petworth or Fort Totten on the Green or Yellow Lines. Yellow and Green line riders should expect delays in both directions.

Metro tweeted these Metrobus routes as alternate options for riders: U St- 90s to RD, 70/79 at Georgia Av; Columbia Hts H2,H3,H4,H6,H8 to RD; Georgia Av 62/63/64 to Ft Totten, 70.

Two other trains were offloaded without problems on the platform at Georgia Avenue, Stessel said.

He did not know the cause of the power problem.