Britain's Parliament has been hit by a new wave of cyber attack after hackers attempted to trick lawmakers into revealing their passwords, prompting officials to warn MPs and their aides to guard against such threats.
Politicians have been warned that hackers were posing as parliamentary officials asking for their passwords.
"This afternoon we've heard reports of parliamentary users being telephoned and asked for their parliamentary username and password," a message sent to MPs and staff earlier this week warned.
"The caller is informing users that they have been employed by the digital service to help with thecyberattack. These calls are not from the digital service. We will never ask you for your password."
According to 'The Sunday Telegraph', parliamentary officials have said that hackers are still attempting to gain access after a "sustained" assault last week lasted for more than 12 hours as unknown hackers repeatedly targeted "weak" passwords of staff.
Security sources told the newspaper the attack was the biggest they could remember.
The network affected is used by every MP, including British Prime Minister Theresa May, and her Cabinet ministers, for dealing with constituents.
It remains unclear whether the hackers were successful in gaining access as the investigation is ongoing.
The UK Cabinet Office, which blamed human error for the breach, said the details were publicly available on data.Gov.Uk, which publishes charts and graphs of public data and is widely used across UK government circles.
A parliamentary spokesperson said: "On Thursday afternoon a small number of parliamentary users were telephoned and asked for their parliamentary username and password by a caller claiming to be employed by 'Windows' on behalf of the Parliamentary Digital Service to help with the cyber attack.
"No usernames or passwords were disclosed in these calls.