The website of Radio Pakistan, the national state broadcaster, was briefly hacked on Sunday, Dawn reported.
A message on the website read: "Hello Admin, you are very secured. Appreciated your security. We got an eye on you. Expect us. Pakistan zindabad."
The hack was also announced on a Twitter account with the handle @TheCrashRulers.
"@RadioPakistan Radio Pakistan Website Hacked by Team #CrashRulers," the tweet said.
It is not confirmed if the account is operated by those behind the hack.
The website has been restored.