Six years later，in an about-face，the FBI admits that federal agents fired tear gas canisters capable of causing a fire at the Branch Davidian compound near Waco，Texas in 1993.But the law enforcement official said the firing came several hours before the structure burst into flames，killing 80people including the Davidians’leader，David Koresh.
’In looking into this，we’ve come across information that shows some canisters that can be deemed pyrotechnic in nature were fired—hours before the fire started，’the official said.’Devices were fired at the bunker，not at the main structure where the Davidians were camped out.’
The Federal Bureau of Investigation maintains it did not start what turned to be a series of fiery bursts of flames that ended a 51-day standoff between branch members and the federal government.’This doesn’t change the bottom line that David Koresh started the fire and the government did not，’the official said.’It simply shows that devices that could probably be flammable were used in the early morning hours.’
The law enforcement official said the canisters were fired not at the main structure where the Davidian members were camped out but at the nearby underground bunker.They bounced off the bunkers concrete roof mad landed in an open field well，the official said.The canisters were fired at around 6a.m.，and the fire that destroyed the wooden compound started around noon，the official said.The official also added that other tear gas canisters used by agent that day were not flammable or potentially explosive.
While Coulson denied the grenades played a role in starting the fire，his statement marked the first time that any U.S.government official has publicly contradicted the govemment’s position that federal agents used nothing on the final day of the siege at Waco that could have sparked the fire that engulfed the compound.The cause of the fiery end is a major focus of an ongoing inquiry by the Texas Rangers into the Waco siege.

The FBI official has NOT admitted that（）.

A．the canisters were fired at the main structure
B．the canisters were fired hours before the fire started
C．federal agents fired tear gas canisters capable of causing a fire
D．other tear gas canisters that were not flammable or potentially explosive were also used