The L.A. Times reports that Islamic State, the group variously known as ISIL, ISIS, and Daesh, has claimed responsibility for the multi-pronged terror attack yesterday in Paris which left at least 128 people dead, most of them from among the audience of a rock concert at the Bataclan theater, in the heart of the city. Details of how Friday’s assaults were carried out remained hazy. It was still unclear, for example, whether the restaurants and concert theater were attacked by two separate teams of militants or one group that went from one place to another. ... Attackers opened fire on the crowd with automatic weapons, shouting “God is great!” or blaming France for airstrikes on Islamic State in Syria, according to some reports. Dozens of concert-goers were killed before French forces stormed the theater. Many Parisians posted appeals and photos on social media asking for news of friends or loved ones whom they had not heard from since the attacks. One man said on Twitter that a government hotline set up to inquire about missing persons was so overloaded that calls could not get through. In the wake of the attacks and with an overloaded public infrastructure, Facebook activated its post-disaster check-in tool for Parisians to notify loved ones that they are safe. According to Reuters, French President Francois Hollande has vowed to undertake a "mercliess" response to the attacks.