American technology giant Yahoo announced that over 1 billion of its website accounts have been hacked into allowing the hackers access to its users’ information. Apparently, the cyber-attack occurred three years ago, but US law enforcement only discovered the incident one month ago notifying Yahoo, who knew nothing regarding the events.

Yahoo headquarters in California

Yahoo headquarters in California Photo Credit: Reuters/Channel 2 News

Last night (Thursday), American technology giant Yahoo announced that more than 1 billion of their account holders’ information has been stolen, making this the largest cyber-attack in history. The cyber-attack exposed last night has no connection to the cyber-attack that the company suffered three months ago, when JOL reported that 500 million Yahoo accounts had been hacked. The company’s shares plummeted by 1.35% in mere hours.

The hacking that was revealed last night most likely occurred in August 2013. Yahoo wrote in its blog that it was completely unaware of the cyber-attack until last month, when US law enforcement provided the company with proof that an unauthorized third party was able to access more than 1 billion users’ account information.

“We are taking measures towards securing users’ information and we are working closely with law enforcement,” the company stated in response to the cyber-attack’s reveal. However, Yahoo has admitted that the hacker’s identity is still unknown.