The victims have been identified by state police as William Hampton, 68, of Indian Orchard, Massachusetts; Chad Davidson, 29, of Woodstock, Connecticut; and Frederika Ballard, 53, of Southwick, Massachusetts, according to local outlets.
Ballard was reported to be the owner of Fly Lugu Flight School in Westfield, Hampton was a flight instructor for the school, and Davidson was a student pilot.
Investigators believe that the plane, a Beechcraft 55 Baron twin-engined piston, took off from Barnes Airport in Westfield around 11.06am on Sunday, according to local reports.
Sometime after, a dog walker called the police to say that a small plane had crashed in Greenfield.
Police said the plane had crashed onto a clearing on the side of a wooded mountain on the Greenfield-Leyden town lien in the Leyden Wildlife Area.
Greenfield Police confirmed on Sunday that they were investigating the crash where there had been “no survivors”.
The victims were removed from the plane crash area by the chief medical examiner’s office, NBC10 said.
State troopers secured the scene overnight while waiting for the investigation to resume on the crash by federal, state and local authorities on Monday morning, the outlet said.
The National Transportation Safety Board confirmed they were investigating the crash but told the outlet that they would not speculate on any causes of the crash, saying their final conclusion of the cause would be in a final report released in one to two years.
The Federal Aviation Administration is also reported by local outlets to be looking into the incident.
Over in Poolville, Texas, a similar small plane crash occurred on the same day that went down around 1.15pm.
A twin-engine Cessna 310 – another small plane – crashed with three people on board, NBC5 reported.