The San Carlos Airport was closed Monday afternoon as authorities investigate an accident in which a plane overran the runway, an airport official said.

Two people aboard the small plane were uninjured when the aircraft rolled off the end of a runway while landing around 10:15 a.m., Federal Aviation Administration spokesman Ian Gregor said.

Airport business manager Chris St. Peter said the pilot wasn't able to stop the plane right away upon landing.

The nose of the single-engine Columbia plane, registered to Harry Drajpuch out of Scottsdale, Ariz., ended up in a slough adjacent to the airport, located at 620 Airport Drive, authorities said.

The two people on board got out of the plane without injury, Gregor said.

San Mateo County sheriff's Deputy Rebecca Rosenblatt said the occupants were both men and that the pilot is from Arizona. The pair had flown in from the Los Angeles area, and the pilot was apparently going too fast as the plane landed, she said.

The plane briefly touched down on the landing strip, but then overran the runway and got lodged in the mud in the waterway south of the airport, she said.

FAA investigators responded to the incident, St. Peter said, and the airport will be closed until the investigation is complete and the plane has been removed from the water.

Airport officials did not have an estimate for when airport operations would resume.