The Federal Aviation Administration is investigating a corporate jet pilot's radio transmission that he saw a possible remote-controlled aircraft flying near his jet over Denver, authorities said Wednesday.

"The FAA is investigating the incident and will try to positively identify the object the Citation pilot reported, where it came from and who was operating it," the FAA said in a statement.

The corporate jet, a Cessna Citation 525 CJ1, was flying over Denver on Monday after coming in from Wichita, Kansas, reported CNN affiliate KUSA.

The pilot made a radio transmission to air traffic control about the object, KUSA reported, citing LiveATC.net.

"A remote-controlled aircraft, or what, but something just went by the other way. ... About 20 to 30 seconds ago, and it was like a large remote-controlled aircraft," the pilot said.