WASHINGTON (Reuters) – The Federal Aviation Administration said it is investigating after several flight crews on Saturday received faulty alerts of potentially nearby aircraft on arrival at Washington’s Reagan National Airport.

The FAA said Monday that some of the crews executed go-arounds as a result of the alerts and is investigating why the alerts occurred. There has been intense focus on traffic at the airport after a Jan. 29 fatal collision between an Army helicopter and American Airlines regional jet near the airport killed 67 people.

(Reporting by David Shepardson)