Thousands of Hong Kong-based websites were down for almost seven hours on Monday because of problems with one of the city's main internet domain name registrars.
Some experts warned the shutdown - possibly the first experienced in Hong Kong's history - could represent a potentially serious crisis.
Hong Kong Domain Name Registration yesterday admitted that system problems had affected a substantial number of about 67,000 locally registered websites ending with com.hk between 3am and 10am.
'Not all of the [com.hk] sites were affected but some of them were. I don't have the exact number. As far as I know, this is the first time this has happened,' a company spokeswoman said.
She said engineers were examining the cause of the breakdown, and could not comment until the reason had been identified.