A break in a water main under Connecticut Avenue was reported Sunday night, and officials said they expected that 50 buildings might experience some effects.

The break in a 12-inch diameter main was reported about 9 p.m. between Van Ness and Yuma streets NW, according to DC Water. Completion of repairs was expected by 6 a.m.

It was not clear how many people were affected by the break. There are few single-family or apartment houses on the avenue at the point of the break. However, there are many office buildings and stores. The University of the District of Columbia campus is nearby.