The Senate Judiciary Committee is holding a hearing Wednesday on the deadly shooting at a Florida high school and the FBI’s apparent failure to investigate the accused shooter as questions still remain into how and why law enforcement officials ignored potential warning signs to prevent suspect Nikolas Cruz from opening fire at Marjory Stoneman Douglas High School and killing 17 people last month.

The FBI has already apologized for failing to act on a tip last month from a person who was concerned that Cruz could shoot up a school. CBS News learned Cruz purchased at least seven rifles in the last year.

The Broward Sheriff’s Office has responded to accusations that the agency failed to act on warning signs, failed to adequately respond to the shooting, and didn’t properly train their deputies.

Panelists at Wednesday’s hearing include Florida Sens. Bill Nelson and Marco Rubio, representatives from the ATF, FBI, Secret Service as well as those connected to victims of the Florida shooting. 

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