  Multi-wavelength observations show that Abell 1367 (A1367) is a dynamically
young cluster, with at least two subclusters merging along the SE-NW direction.
With the wide-field XMM-Newton mosaic of A1367, we discover a previously
unknown merger shock at the NW edge of the cluster. We estimate the shock Mach
number from the density and temperature jumps as $M_{\rho}=1.21\pm0.08$ and
$M_T=1.60\pm0.07$, respectively. This shock region also corresponds to a radio
relic discovered with the VLA and GBT, which could be produced by the shock
re-acceleration of pre-existing seed relativistic electrons. We suggest that
some of the seed relativistic electrons originate from late-type, star-forming
galaxies in this region.
