An officer and a passerby performed CPR on the man before paramedics took him to a hospital in critical condition, Dallas police said.

DALLAS — A man was taken to a hospital in critical condition after a Dallas police officer found him unresponsive in a creek near an apartment complex Tuesday night, police said.

Officers responded around 11:40 p.m. to the 5600 block of Spring Valley Road after a report of a man calling for help outside the complex. The first officer to arrive found the man in a nearby creek, according to police.

The officer and a passerby performed CPR until other officers and Dallas Fire-Rescue paramedics arrived. Paramedics continued lifesaving efforts and took the man to a hospital in critical condition, police said.

Police have not said how the man ended up in the creek. The circumstances remain under investigation.