Based on mapping observations with ASCA, an unusual hot region with a spatial extent of 1 square degree was discovered between M87 and M49 at a center coordinate of R. A. = 12h 27m 36s and Dec. = $9^circ18$ (J2000). The X-ray emission from the region has a 2-10 keV flux of $1 times 10^{-11}$ ergs s$^{-1}$ cm$^{-2}$ and a temperature of $kT gtrsim 4$ keV, which is significantly higher than that in the surrounding medium of $sim 2$ keV. The internal thermal energy in the hot region is estimated to be $V n k T sim 10^{60}$ ergs with a gas density of $sim 10^{-4}$ cm$^{-3}$. A power-law spectrum with a photon index $1.7-2.3$ is also allowed by the data. The hot region suggests there is an energy input due to a shock which is probably caused by the motion of the gas associated with M49, infalling toward the M87 cluster with a velocity $gtrsim 1000$ km s$^{-1}$.
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