A person died Monday evening after they appeared to suffer "a medical issue" while in police custody, Watertown police said in a statement.

Police said they attempted to pull over a car for a routine traffic stop, when the passenger jumped out of the car and fled on foot. The person was caught after a brief chase.

While walking back to the police car, the person then suffered the medical event, police said, but the department statement didn't elaborate on the type of medical issue. 

The person was transported to Samaritan Medical Center for treatment and later pronounced dead, according to police.

Police have not released the person's name, gender, age or hometown. The cause of death is also unknown, police said.

The New York State Attorney General's Office will investigate the death, in accordance with state law.