After the terrorist attack in London, the British government said that its security services must have access to encrypted messaging applications such as WhatsApp, as it was revealed that the service was used by the man behind the attack.

The 52-year-old Briton who killed four people in a rampage in Westminster on Wednesday – reportedly used the Facebook-owned WhatsApp, moments before the assault.

Home Secretary, Amber Rudd said “it was completely unacceptable” that police and security services had not been able to crack the heavily encrypted service.

“You can’t have a situation where you have terrorists talking to each other — where this terrorist sent a WhatsApp message — and it can’t be accessed,” she said.

“There should be no place for terrorists to hide,” Rudd said, while talking to the BCC.

“We need to make sure that organisations like WhatsApp — and there are plenty of others like that — don’t provide a secret place for terrorists to communicate with each other.”

She said end-to-end encryption was vital to cyber security, to ensure that business, banking and other transactions were safe — but said it must also be accessible.

Rudd said she doesn’t intend to force the industry’s hand with new legislation, yet, but would meet key players on Thursday to discuss this issue, as well as the “constant battle” against extremist videos posted online.

WhatsApp ‘Horrified’ By The Attack

WhatsApp said it was working with British authorities investigating the Westminster attack, but did not specify whether it would change its policy on encrypted messaging.

“We are horrified at the attack carried out in London earlier this week and are cooperating with law enforcement as they continue their investigations.”

Last year, US authorities fought a legal battle with tech giant Apple to get it to unlock a smartphone used by one of the shooters in a terror attack last year in California.

Meanwhile, Google, has faced a boycott by companies whose adverts appeared alongside extremist content on its video-sharing platform, YouTube.