CHICAGO (CBS) — The Mariano’s grocery in Greektown was evacuated Sunday afternoon after an “unknown substance” was discovered.

The Mariano’s at 40 S. Halsted St., at the intersection with Monroe Street, was evacuated when the Fire Department called a Level 1 Hazmat situation.

The store was also closed to those who wished to come in.

Details about the substance that was found were not immediately released, but the Fire Department said tests on the substance did not show anything dangerous.