The US Federal Aviation Administration is investigating the collision between a 737 and a jet in San Diego.

The Federal Aviation Administration (FAA), America’s main aviation regulator, announced on Saturday that it is investigating the collision between a Southwest Airlines Boeing 737 and a Cessna Citation business jet in San Diego. Shortly before noon Friday, an air traffic controller at San Diego International Airport took instructions to land on the same runway where Southwest Flight 2493 was taxiing and waiting, the FAA said. Airport systems alerted the controller of possible collisions, however, the expert instructed the Cessna to proceed with the landing. A source said the Cessna passed within 100 feet of the Southwest 737. The FAA sent a team to San Diego to investigate the incident. The airline said on Saturday that it was also participating in a review process to determine what happened. “Our flight took off without any problems and the flight proceeded normally, landing safely in San Jose as scheduled,” the company said. The National Transportation Safety Board (NTSB), the agency that investigates airline accidents, has been investigating six similar incidents since January. Something similar happened in Austin, Texas in February, when a FedEx cargo plane and another Southwest 737 narrowly missed a collision by just 35 meters amid poor visual conditions. FedEx allowed simultaneous landings and Southwest departures.