Police protocol for hostage situations during terrorist attacks may need to change in the wake of the Orlando Pulse nightclub massacre last year, according to the group hired by the U.S. Department of Justice to review the Orlando attack.

Local law enforcement agencies should create policies specifically for terrorism involving suicide bombers or hostage situations, researchers from the Police Foundation suggested in a new journal article that examines lessons from the mass shootings in Orlando — where 49 people died — and San Bernardino, Calif.

The article addresses concerns about why Orlando Police waited more than three hours to confront gunman Omar Mateen, who called 911 during the June 12 attack to declare his allegiance to ISIS while holding some of the survivors hostage, the Orlando Sentinel reports.

“It should be stressed ... that the police responding to the attack followed protocols and best practice for hostage situations …” the researchers wrote. “Recognizing that the threat of such extremist terrorism represents a continuing, if not growing threat, it may be appropriate to develop specific protocols for hostage events during terrorist attacks.”