The intersection of 18th Street and Columbia Road NW is closed and two people are injured after a car drove into the McDonald’s in Adams Morgan. (Clinton Yates/The Washington Post)

A vehicle crashed through the front of the McDonald’s restaurant in the heart of the Adams Morgan area Friday, injuring two people, damaging the building and blocking traffic for hours, D.C. authorities said.

The crash occurred about 2:30 p.m. at 18th Street and Columbia Road NW, one of the busiest and best-known intersections in the District.

One of the injured people was the driver of the vehicle, said Lon Walls, a spokesman for the D.C. fire department. He was taken to a hospital with injuries considered serious but not life-threatening, Walls said. Also injured was a female McDonald’s customer, Walls said. She was taken to a hospital with injuries that were regarded as minor.

No official cause of the crash was available. However, there were signs that it might have stemmed from a medical condition affecting the driver, said Officer Hugh Carew, a D.C. police spokesman.

Buildings are struck by cars relatively often, sometimes as a result of medical problems.

Witnesses and photographs indicated that the vehicle penetrated the restaurant as far as its windshield. When it was pulled out, its front end showed considerable damage.

Damage to the restaurant doorway “was so extensive, I thought there had been an explosion,” said a woman who arrived at the scene about an hour after the crash.

Someone inside at the time reported online: “There was a huge crash behind me and all I could see was dust, broken glass and the hood of the car. . . . Everyone was running around”

According to authorities, it was at the same McDonald’s that events occurred that led to the fatal Nov. 17 stabbing in the Woodley Park Metro station.