BALTIMORE — (CNN) Fearing more unrest as pretrial hearings begin for six officers charged in the death of Freddie Gray, the Baltimore Police Department has canceled leave.

“We would rather err on the side of caution and have an abundance of people readily available as needed,” Lt. Sarah Connolly said. “We are hoping we don’t need them.”

Gray’s death while in police custody in April ignited nights of widespread violence across the city. Police officers were injured and businesses destroyed.

Attorneys representing the officers facing charges in Gray’s death are working on a number pretrial motions, including a dismissal of all charges, a change in venue and having the state’s attorney’s office removed from the case.

Community activists have called for demonstrations this week and next.

The trial of the “Freddie Gray Six” is scheduled to begin in October.

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