Council Bluffs Police say they located three people who were unconscious near the D & S Express gas station Tuesday night around 10 p.m..
A half hour later Police say they found a man at a home a few blocks away.
All four people went to area hospitals and are suspected of overdosing on Fentanyl.
One of them is no longer receiving treatment.
Fentanyl is a drug that can be extremely dangerous even for an accidental exposure.
Police are investigating the incidents.