Fetus was discovered by a cleaning crew Tuesday morning.
The fetus was believed to be five or six months along.
According to CBS reports, the American Airlines flight arrived at LaGuaradia Airport from Charlotte, North Carolina shortly before 10:45 p.m. It was the Airbus A321's only flight of the day.
The Office of the Chief Medical Examiner in NY confirmed it is "investigating what we believe to be a human fetus found deceased on an airplane", said Aja Worthy-Davis, executive director for public affairs. "Please contact law enforcement for additional information". "We will release cause and manner of death upon determination." .More news: Oman issues statement on Saudi-Canada stand-off
The plane was later pictured being moved to a hanger as law enforcement began investigating the find.
The Queens County District Attorney is looking into the matter.
The account later tweeted to a frustrated customer that planes may be delayed "due to the medical needs of a customer".
LaGuardia Airport warned via Twitter shortly after 8 a.m. Tuesday that flyers traveling out of B gates may experience some delays because of an "out of service airplane", which was code for police activity surrounding the plane.