Baltimore police revealed Thursday morning in a news conference that a transport van carrying Freddie Gray, the 25-year-old black man who suffered a severe spinal injury in police custody, made one more stop than was previously known.

The city has been riled by protests and pockets of violence since Gray succumbed to his injures a week after his April 12 arrest. Police have so far been unable to explain how Gray sustained the spinal injury, although they’ve indicated that they believe it happened while Gray was inside the van en route to the Western District police station.

Deputy Police Commissioner Kevin Davis said police found out about the new stop from video footage captured on a privately owned surveillance camera. According to the timeline Davis laid out, the new stop is the second of four stops the van made on April 12.

The van first pulled over to complete paperwork after the driver believed Gray began acting “irate.” Then the van made a second, previously unknown stop (Davis did not elaborate on what occurred during this new stop). At a third stop, an officer had “some communication” with Gray, which was under investigation. The van then picked up another arrestee at a fourth stop before completing its trip to the Western District police station, where a medic was called to respond to Gray.

Police Commissioner Anthony Batts also said in the news conference that the agency had turned its investigation over to the state attorney’s office, although the department would continue to investigate if any new evidence or witnesses emerged.

Batts has previously acknowledged that officers should have called for medical attention for Gray when he was first arrested and not once he arrived at the Western District station. He has also said officers failed to put a seat belt on Gray while he was in the transport van as required by department policy.