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We performed a systematic X-ray study of eight nearby $\gamma$-ray brightradio galaxies with {\em Suzaku} for understanding the origin of their X-rayemissions. The {\em Suzaku} spectra for five of those have been presentedpreviously, while the remaining three (M\,87, PKS\,0625$-$354, and 3C\,78) arepresented here for the first time. Based on the Fe-K line strength, X-rayvariability, and X-ray power-law photon indices, and using additionalinformation on the [O III] line emission, we argue for a jet origin of theobserved X-ray emission in these three sources. We also analyzed five years of{\em Fermi} Large Area Telescope (LAT) GeV gamma-ray data on PKS\,0625$-$354and 3C\,78 to understand these sources within the blazar picture. We foundsignificant $\gamma$-ray variability in the former object. Overall, we notethat the {\em Suzaku} spectra for both PKS\,0625$-$354 and 3C\,78 are rathersoft, while the LAT spectra are unusually hard when compared with other$\gamma$-ray detected low-power (FR\,I) radio galaxies. We demonstrate that theconstructed broad-band spectral energy distributions of PKS\,0625$-$354 and3C\,78 are well described by a one-zone synchrotron/synchrotron self-Comptonmodel. The results of the modeling indicate lower bulk Lorentz factors comparedto those typically found in other BL Lac objects, but consistent with thevalues inferred from modeling other LAT-detected FR\,I radio galaxies.Interestingly, the modeling also implies very high peak ($\sim 10^{16}$\,Hz)synchrotron frequencies in the two analyzed sources, contrary topreviously-suggested scenarios for FR I/BL Lac unification. We discuss theimplications of our findings in the context of the FR\,I/BL Lac unificationschemes.

Suzaku and Fermi Observations of Gamma-Ray Bright Radio Galaxies: Origin of the X-ray Emission and Broad-Band Modeling