A replica grenade used to grind marijuana closed a Vancouver Island airport for almost four hours Wednesday morning after it was found inside a passenger's checked luggage.

The passenger terminal at Campbell River Airport was evacuated shortly after 6:30 a.m. after an X-ray scan revealed the suspicious metal item inside a piece of luggage.

Police called in explosives experts from Vancouver and scheduled flights were re-routed to Comox while the bomb squad investigated.

The airport re-opened at 10:20 a.m. after police determined that the grenade was merely a replica -- a grinder used to crush organic material like marijuana.

RCMP officers detained two men in connection with the grenade, but they have since been released from custody. No charges are expected.

"This just shows how a lapse in judgment can have tremendous consequences," RCMP Const. Alexa Blacklock said in a press release.

"It forced an enormous unnecessary use of resources, including specialized units, fire, police and security staff."