A security incident is 'ongoing' at the Royal Navy's warfare school, HMS Collingwood in Fareham.
It is thought that the incident could involve a suspicious package but the MoD have not confirmed this.
A spokesperson said, "We can confirm there is an ongoing incident at HMS Collingwood, the Royal Navy warfare school in Fareham, Hampshire.
"It would be inappropriate to comment further at this stage."
HMS Collingwood is the headquarters of the navy's Maritime Warfare School and Surface Stream, delivering training including weapon engineering, diving,physical training, chemical biological radiation nuclear and damage control, sea survival, seamanship and military skills.
More top news
Dry with clear spells overnight. Dry and breezy with sunny spells for much of tomorrow. Rain arriving later. Becoming humid from Monday.
Showers fading away with clear spells overnight. Dry with sunny spells for much of tomorrow with rain arriving later. Becoming humid later.
Feeling warm in this afternoon's sunshine. Breezy at times with the risk of an isolated shower.