Did federal agents start the conflagration in which 75 Branch Davidians died near Waco, Texas, on April 19, 1993? That question has been raised by many journalists as well as by paranoid militia groups and conspiracy theorists on the extreme right. Now it's being pursued by the U.S. government. Attorney General Janet Reno has directed former Senator John Danforth to investigate reports that the FBI tossed flammable grenades into the Branch Davidian compound. Danforth will also be investigating whether federal sharpshooters opened fire on the religious group that day. The FBI has denied such shootings, and though it has admitted launching several incendiary devices, it insists that these grenades did not start the fatal fire.