A naval base in the Australian state of Victoria is in lockdown and a resident of the base is in custody, with a police bomb squad heading to the scene to investigate unspecified 'hazardous material', security officials said on Thursday. An exclusion zone of 400 meters had been declared around a residential apartment at HMAS Cerberus, a naval training base on the Mornington Peninsula, 75 km (45 miles) southeast of Melbourne, Victorian police said. Police took the security measures after a routine search of the apartment found a number of unspecified items on Thursday morning. A statement from the Australian Defense Force said 'hazardous material' had been found, but gave no further details. A bomb response unit and members from the arson and explosives squad were en route, a Victorian police spokeswoman told Reuters. The resident was understood to be in the custody of other naval officers, the spokeswoman added.