In 1940, Antrea became a part of newly established Yaskinsky District with the administrative center in the work settlement of Yaski. At the same time, it was granted town status. At that time, it was a part of the Karelian ASSR (after March 30, 1940 of the Karelo-Finnish SSR). On November 24, 1944, Yaskinsky District was transferred from Karelo-Finnish SSR to Leningrad Oblast. To replace Finnish names of the localities with Russian names, on October 1, 1948, the district was renamed Lesogorsky and the town of Antrea was renamed Kamennogorsk. The town's new name was due to the presence of crystalline deposit outcrops and a granite mine in the vicinity.