DETROIT (WJBK) - UPDATE 5:00 PM: Fox 2's Ingrid Kelley finds that the projectiles were discovered by a janitor.
The bomb squad and FBI were brought in as investigators worked to identify the items and learn if they could be explosive military materials.
Residents living near the school were advised to stay in place.
No one was injured and the school released a statement saying they are extremely grateful for the quick response from Detroit emergency personnel.
UPDATE 1:45 PM: Several projectiles have been recovered and removed from a garage on school grounds by the bomb squad.
Officials tell Fox 2 that the items appear to be from the Vietnam War era.
Each of the projectiles is measured at 75 millimeters.
Police say the garage had not be inventoried in more than 30 years.
UPDATE 11:25 AM: Students at the school were moved to Callahan Hall on school grounds as the Detroit bomb squad inspects the suspicious package found by maintenance crews.
Students and staff are being evacuated at a Catholic school in Detroit after maintenance crews found what is believed to be WWII era explosive devices.
Gesu Catholic School was evacuated around 10:45 Monday morning when maintenance found the items in a garage on school grounds.
The school is located at 17139 Oak Drive on Detroit's west side near McNichols and Livernois.
Emergency crews are on the scene checking to make sure these items are not explosive.
This story is developing - stay with Fox 2 for details.