Britain's Royal Navy was forced to take down its website after it was disrupted by hackers, the Ministry of Defense said on Monday.
A message on the website reads: "Unfortunately the Royal Navy website is currently undergoing essential maintenance. Please visit again soon."
It comes just weeks after the government announced a 650 million pound ($1.05 billion) national cyber security programme.
"We can confirm that there was a compromise of the RN web over the weekend," a Royal Navy spokesman said in a statement.
"There has been no malicious damage; but as a precaution, the RN website has been temporarily suspended. Security teams are investigating."
It was not clear when the site would be back up and running.