(Recasts with news conference, adds quotes, details on passenger rail service disruptions)

By David Lawder

WASHINGTON, May 1 (Reuters) - A CSX freight train derailed in northeastern Washington on Sunday, spilling hazardous material near a subway station and disrupting commuter rail and long-distance Amtrak passenger trains but causing no injuries, authorities said.

Thirteen rail cars were strewn across the tracks at the derailment site in the early morning incident, District of Columbia Fire Department photos showed.

A ruptured tank car likely leaked several hundred gallons of sodium hydroxide, a caustic substance used to produce household products including paper and detergent, before the leak was plugged, Deputy Fire Chief John Donnelly told a news conference.

The fire department did not order evacuations around the site of the accident, which happened about 3 miles (5 km) from the White House near the elevated Rhode Island Avenue station.

Washington Mayor Muriel Bowser said it would take some time for CSX and emergency workers to clear the overturned cars and clean up the spill.

"There's nothing running on that track tomorrow," Bowser said.

She added that no cause for the accident had been determined, but a federal investigation into the derailment had begun.

The derailed train was traveling from Cumberland, Maryland, to Hamlet, North Carolina. It was made up of three locomotives and 175 rail cars.

Amtrak spokeswoman Vernae Graham said the Chicago-to-Washington Capitol Limited long-distance trains would terminate in Pittsburgh, with Washington passengers given alternate transportation until the area was cleared.

Amtrak's electrified Northeast Corridor trains were not affected, as they use a different set of tracks.

The Maryland Transit Administration said its MARC Brunswick Line commuter trains on Monday from Martinsburg, West Virginia, to Washington would likely terminate at Silver Spring, Maryland.

The station was shut down and Red Line subway trains were not allowed through the area on Sunday. A spokesman for the region's Metro transit system said service would be restored as soon as the hazardous materials were cleared from the area and safety tests conducted on the Metro rails.

The chemical spill could stir controversy over CSX transporting hazardous materials through the heart of the U.S. capital. Over the past five years, some District residents and community groups opposed a major CSX construction project to rebuild and expand a 112-year-old rail tunnel in central Washington, fearing it would encourage more freight traffic through the city and increase chances of a chemical spill.