A military object found in a Polish forest in April was a Russian KH-55 missile, two Polish media outlets reported on Wednesday.
Poland has been on alert for possible spillover of weaponry from the war in neighbouring Ukraine, especially since two people were killed near the border last November by what Warsaw concluded was a misfired Ukrainian air defence missile.
Polish authorities said last month a "military object" had been found in a forest close to the village of Zamosc near the northern city of Bydgoszcz, without going into further details about its origin.
Prosecutors also said at the time that no trace of any explosion had been found at the site, which was hundreds of kilometres from Poland's borders with Ukraine, Belarus and the Russian exclave of Kaliningrad.
Private broadcaster RMF FM reported on Wednesday without naming its sources that the preliminary findings of Poland's Air Force Institute of Technology was that the object was a Russian KH-55 missile.
Private broadcaster Polsat News also reported without naming its sources that the object was a KH-55 missile.
The KH-55, which is refered to as CH-55 in Polish, is an air-launched cruise missile developed by the Soviet Union that is capable of carrying a nuclear warhead.
A Polish government spokesman and the Air Force Institute of Technology could not immediately be reached for comment. The Polish defence ministry and Russian embassy in Warsaw declined to comment.
(Reporting by Alan Charlish, Pawel Florkieiwcz and Anna Wlodarczak-Semczuk; Editing by Nick Macfie and Angus MacSwan)
