Results of instrumental observations of the Koyna earthquake of 1967 December 10 have been generalized in this paper.First arrival times of seismic waves recorded in the distance range of 0.03" to loo" have been used. A set of origin locations has been found from different samples of the seismic observations. The data obtained suggest the origin extension as being 20-25 km in the horizontal direction and 60-80 km in the vertical one. The limits of the focal region have been fixed by systems of near and teleseismic stations.Dynamic parameters of seismic waves at teleseismic stations give evidence of radiation from a deep source.