A militant group calling itself the Al-Nusra Front claimed responsibility on Friday for suicide attacks earlier in the week that took 55 lives. The bombings in Damasus were in retaliation for attacks on civilian areas by President Bashar al-Assad and his forces, the militants said in the video. “We fulfilled our promise to respond with strikes and explosions,” a speaker in the video said. Western officials have become increasingly worried about the presence of extremist groups and Islamic militant in the evermore destabilized country. Little is known about Al-Nusra Front, but some intelligence experts suspect it could be a proxy for al Qaeda.