Twitter warns users of state-sponsored hacker attacks

Twitter has issued an alert to some users warning them that state-sponsored hackers might have tried to obtain sensitive data from their accounts, the micro-blogging site said, in the first such warning by it.

According to the notice, there was no indication the hackers obtained sensitive information from a "small group of accounts" targeted.

The warning also did not provide additional information about the attack or possible suspects in its investigation.

Twitter's notice comes as the latest amid concern about cyber attacks by state-sponsored organisations. Government agencies, businesses and media had all been hacked.

The warning had been reported earlier by The Finanical Times and tech news site Motherboard.

According to Coldhak, a Winnipeg-based non-profit, which had received the notice,  the warning from Twitter on Friday said the attackers might have been trying to obtain information such as "email addresses, IP addresses, and / or phone numbers".

Coldhak's Twitter account, @coldhakca, retweeted reports from a several other recepients of notice, but they did not not indicate why they might have been singled out.

Colin Childs, one of the founding directors of Coldhak, told Reuters his organisation had seen "no noticeable impact of this attack".

A spokesman for San Francisco-based Twitter confirmed the authenticity of the emails.

According to commentators, the warning, like similar ones issued by Facebook and Google earlier, point to the growing frequency of state-sponsored hacks.

China and the US had over the years been accusing each other of high-tech espionage. Even the involvement of the North Korean government was suspected in a hack on Sony Entertainment, which exposed the inner workings of the studio.

Social media had increasingly emerged as a battlefield for hackers in recent years. The Syrian Electronic Army, a hacking group backing the regime of Syrian president Bashar al-Assad, had claimed responsibility for several hacks of news sites and company web sites.