Updated at 12:45 p.m. ET

The death of Baltimore man Freddie Gray was the result of a "high-energy injury" to his spine and was ruled a homicide due to "acts of omission" by police, according to The Baltimore Sun. The newspaper cites a copy of the unreleased autopsy report from the state medical examiner's office.

Gray, 25, died in a hospital in April, after being taken into police custody and put in a police van. The case — one of a string of high-profile incidents in which U.S. police killed unarmed black men — outraged the local community and eventually resulted in rioting that prompted the National Guard to be deployed in Baltimore.

The Sun reports:

"Though Gray was loaded into the van on his belly, the medical examiner surmised that he may have gotten to his feet and was thrown into the wall during an abrupt change in direction. He was not belted in, but his wrists and ankles were shackled, putting him 'at risk for an unsupported fall during acceleration or deceleration of the van.' "

The newspaper adds that the medical examiner compared Gray's injury to one that someone might sustain if they dove into shallow water.

An excerpt of the autopsy report that was published by The Sun explains the homicide finding:

"Safety equipment was available but not used. Therefore, it was not an unforeseen event (a medico-legal definition of an accident) that a vulnerable individual was injured during operation of the vehicle, and that without prompt medical attention, the injury would prove fatal."

Copyright 2016 NPR. To see more, visit http://www.npr.org/.