Аннотация:This paper presents ana analysis of operation of the gamma-telescope, on board of Cosmos-251, 264 and 280 satellites to detect gamma-rays with Eg>100 MeV. An additional gamma-radiation source has been searched for in the regions of the sky with the known local radio radiation sources (Cygnus-A, Virgo-A, the Crab Nebula, 3C273, 3C120, etc.).
The gamma-ray flux ~5x10-4 photons/cm2/s has been observed in the vicinity of 3C120. The time of measurements coincide with outbursts of radiation coming from 3C120.
If the registered gamma-ray flux comes from 3C120, the magnitude of outbursts of the latter in the gamma-rays is ~2x10*47 erg/sec.