Update, 8:58 a.m.:
All lanes have been opened.
Update, 8:11 a.m.:
Lanes going south on Montana Avenue are open. One northbound lane remains closed.
The 1800 block of Montana Avenue in Northeast is closed in both directions due to a missing manhole cover and a vehicle oil leak, police said.
Police said Montana Avenue is closed between 18th Street and the intersection of Montana Avenue NE and New York Avenue.
At 7:46 a.m. traffic access remained closed. Metrobus route E2 to Friendship Heights may experience delays.