A police bomb squad found nothing suspicious about materials discovered in a sailor's room that led to the lockdown of a naval base southeast of Melbourne, police say.

A 400-metre exclusion zone was set up around the barracks at HMAS Cerberus at Crib Point earlier in the day as officers investigated "hazardous" materials found in the 30-year-old able seaman's barracks.

He was questioned by officers but had since been released.

Police said they did not find anything suspicious and handed the matter back to the Defence Force.

Earlier, Superintendent Neil Paterson from Victoria Police said while he could not go into detail about the materials, they did not appear to be explosives.

"It's not a large number of materials, but the materials that have been found are hazardous and not normally found in barracks at this location," Superintendent Paterson said.

"Navy staff have conducted a routine barracks inspection, found some potentially hazardous material and have notified Victoria Police.

"They are generally not found together, they are of concern to us and ... our bomb squad is on site and will conduct an investigation."

No terrorism link, immediate threat: police

He said there was no suggestion of malicious intent and dismissed suggestions the find could be related to terrorism.

The sailor was not thought to share his room with anyone at HMAS Cerberus, police spokesman. ( ADF: ABIS Cassie McBride )

"There has been no immediate threat, given the nature of the materials and no life has been at threat here on the site.

"The base is secure at the moment, we have set up an exclusion zone. The personnel staff that are on the base are very safe indeed.

Superintendent Paterson said police did not believe the sailor - an able seaman - shared his room with anyone else.

The Navy's website said about 6,000 people were trained at the base annually and about 800 trainees were on the premises at any given time.

The facility covered 1,500 hectares.