The discovery was made around 2:45 a.m. in the 500 block of Adams Avenue.
A green military type container about 1 foot by 1 foot was found outside, officials say.
The Ordinance Disposal Unit opened the container and found some type of propane like camping canisters inside.
The crews safely removed the container from the area.
Police say they are questioning a man in connection with the container about allegations that he had a dispute with someone at Planet Fitness.
So far, there have been no charges filed.