Taiwan has mistakenly fired a supersonic anti-ship missile, according to an official Taiwanese news agency.

The Central News Agency said the 500-tonne patrol boat Chinchiang was undergoing an inspection inside a military base when the missile - a Hsiung Feng III - was fired by accident on Friday.

There were no injuries caused by the error.

It said the missile landed in waters off the islands of Penghu near Taiwan and that a preliminary investigation showed that its operators may have failed to follow proper procedures.

The agency said a full investigation is under way.