A CSX freight train derailed in northeastern Washington, D.C., on Sunday, spilling hazardous material near a city subway station, and emergency workers were cleaning up the site after plugging the leak, officials and the railroad company said.

Thirteen cars were overturned in the early hours of the morning but there were no injuries. The substance that leaked was sodium hydroxide, used to produce household products including paper, soap and detergent.

"We don't know how much leaked. That's the process, trying to figure that out. The fumes should not cause you any problems," District of Columbia Fire Department Deputy Chief John Donnelly said at a news conference.

The District fire department did not order evacuations around the site of the accident, which happened near a city subway station and about 3 miles from the White House.

But the Rhode Island Metro Station and Rhode Island Avenue, and other nearby streets were shut down so that emergency officials could access the site, and to make sure there was no danger from the spill.

Fire department photographs showed several cars lying on their sides by the tracks on the main train route into the city, including tank cars, bulk material cars and box cars.

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 D.C. residents and community groups had opposed a major CSX construction project to rebuild and expand a 112-year-old rail tunnel in central Washington, fearing that it would encourage more freight traffic through the city and increase chances of a chemical spill.

The $170 million project will replace the single-track tunnel with a taller, twin-track version that will allow trains carrying double-stacked shipping containers. Construction is now underway following several unsuccessful court challenges.

The derailed train was traveling from Cumberland, Maryland, to Hamlet, North Carolina. It was made up of three locomotives and 175 rail cars, some carrying mixed freight and some riding empty, Washington Mayor Muriel Bowser said at the news conference.

According to the U.S. Centers for Disease Control and Prevention website, sodium hydroxide is a caustic soda. It is white, odorless and solid at room temperature, usually stored as flakes, beads or in granular form.

Bowser said she had not been notified whether the National Transportation Safety Board would be involved with investigating the derailment, but she said an official from the Federal Railroad Administration was on the scene.