Taiwan's military prosecutors were investigating the disappearance of two maps containing secret information on the island's naval deployments, reports said Saturday.

The maps were found to be missing during an inventory check by naval officials when a fleet of ageing missile boats was recently decommissioned, said the state Central News Agency.

The navy has asked military prosecutors to investigate the incident while instructing all relevant units to tighten management of confidential information, the report said.

The United Daily News cited unnamed sources as saying that the maps contained secret information, including the deployment of Taiwanese naval vessels in the event of a war that would "render the navy naked to its enemy."

Separately, prosecutors were looking into the case of two laptop computers belonging to another type of missile boat that had gone missing since late May, reports said.

Navy officials were not immediately available for comment.