We have studied a number of galactic open clusters that lie in the err
or boxes of COS B sources. These clusters belong to complexes in which
similar star formation processes occur. They have similar ages, stell
ar population and contain peculiar stars with very high-velocity stell
ar winds. We propose that a system of shock fronts, set up at the inte
rfaces between the hypersonic wind of the peculiar stars and the other
cluster members, generates acceleration of cosmic ray particles, whos
e interactions with the inter-cluster gas concentrations would be resp
onsible for the observed gamma-ray emission. We find various observati
onal evidences (including CGRO data, strongly supporting the associati
on of the gamma-ray source J 2021+37=2CG075+00 with Berk 87) for the p
resence of such shock fronts in some of these clusters. We show that t
he diffuse hard X-ray emission from the clusters regions is consistent
with the geometric scenario inferred from the data and with the assum
ed mechanism of cosmic ray acceleration.