Fighter jets escort American Trans Air flight

NEW YORK (CNN) -- An American Trans Air flight Tuesday night was escorted by fighter jets to New York's LaGuardia Airport after a passenger reported suspicious activity by fellow passengers, a transportation official said.

The passenger noticed several others on the Chicago to New York flight, passing notes and changing seats, according to a Port Authority spokesman. The passenger notified a flight attendant, who told the pilot. After aviation authorities were alerted, the plane was escorted to LaGuardia by two military F-16s, the spokesman said.

Flight 204 with 98 passengers on board landed without incident shortly before 11 p.m. ET.

Four men and three women were questioned and then released by police. They are part of a "traveling entertainment troupe," a Port Authority spokesman said.