Police said that the devices were brought with prior notification into a fire station across the street from one of the airport’s cargo terminals, which houses the Delta Airlines’ and KLM Royal Dutch Airlines’ cargo facilities.
Police said in an updated alert on Monday the evacuation was carried because of what turned out to be three World War II-era military-grade devices.
The devices have been secured and removed by the Explosive Disposal Unit, the alert said.
Police added that the evacuation was ordered out of an abundance of caution after authorities determined that the ammunition was live.
The road closures in the area have now been lifted.
Originally police were called to the scene at 3:55 pm local time (7:55 p.m. GMT).