Perth's Elizabeth Quay train station was evacuated after a package was left unattended on Wednesday afternoon.

A caller on Ollie Peterson's Perth Live program said there were about 100 people outside the station at 3pm, just before the peak hour commute.

Perth commuters can expect delays on the Mandurah line. Credit:David Allan-Petale

"There are train operators are looking into the tunnel," the caller said.

"Four policemen arrived, one is looking down (the tunnel as well). Obviously something is going on that is a bit more serious."