Hawaii man who sent missile alert says he's devastated by mistake

The ex-Hawaii employee who sent a false missile alert last month says he's devastated about causing panic, but he believed it was a real attack at the time.

The man in his 50s spoke to reporters on Friday on the condition he not be identified because he fears for his safety after receiving threats.

He says the on-duty call he received on January 13 didn't sound like a drill. However, state officials say other workers clearly heard the word "exercise" repeated several times.

He said it felt like he had been hit with a "body blow" when he realised it was just a drill and he has had difficulty eating and sleeping since.

The agency fired him.