UPDATE 5:11 p.m.:

Previous reports of local authorities having detained one of the three suspects have been rescinded, meaning all three individuals are currently at large and still considered dangerous.

UPDATE 1:17 p.m.:

Local authorities reportedly have one of the three suspects in custody. The remaining two individuals are believed to be still on the loose, according to CNN.

See original story below.

A police officer was killed on Tuesday following a foot chase of some sort in Lake County, a suburb on the outside of Chicago. The officer reportedly called for backup before being found dead from a gunshot wound and stripped of his equipment, according to the Associated Press. A massive manhunt is currently underway for the three suspects, including helicopters and officers on foot:

Lake County Sheriff's Office spokesman Sgt. Christopher Covelli says the officer radioed in Tuesday morning to tell dispatchers he was chasing three men on foot, but communication with him was lost shortly after.

Covelli says the officer's backup arrived to found him injured with a gunshot wound and that the officer died at the scene.

The suspects are considered armed and dangerous, though no definitive descriptions aside from "two white males and a black male" have been released:

A K-9 unit associated with the search team has reportedly "picked up a scent" near a swampy area off Rainier Way and Rollins Road, according to CBS News. The identity of the deceased officer has not been released, though he was revealed to be a 32-year veteran of the force.

This story is developing.