British security services on Sunday asked the creators of the popular messaging service WhatsApp for help in accessing one of the final communications sent by Westminster Bridge terroristKhalid Masood, Fox News reports.
Masood sent an encrypted message on WhatsApp just minutes before he began the rampage that killed three pedestrians and a police officer and wounded dozens of others.
Home Secretary Amber Rudd urged those behind WhatsApp -- and similar apps -- to make their platforms accessible to intelligence services.
"We need to make sure that organizations 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, according to Fox News.
Rudd did not provide any details about Masood's use of WhatsApp, saying only "this terrorist sent a WhatsApp message and it can't be accessed."
The British plea mirrors one made by the FBI following the San Bernardino terror attack in December 2015. After that incident, investigators asked Apple to help unlock one of the terrorist's iPhones, but to no avail.
Eventually, the FBI found its own way to unlock the device.
While police said on Saturday that Masood acted alone, they are trying to pinpoint his motive and identify any possible accomplices, making the WhatsApp message a potential clue to his state of mind and his social media contacts.
Rudd said attacks like Masood's would be easier to prevent if authorities could penetrate encrypted services after obtaining a warrant similar to the ones used to listen in on telephone calls or — in snail mail days — steam open letters and read their contents.
Without a change in the system, she warned, terrorists would be able to communicate with each other without fear of being overheard even in cases where a legal warrant has been obtained.
The Islamic State (ISIS) group claimed responsibility for Wednesday’s terror attack, but it is unclear whether ISIS directed Masood or merely inspired him. Fox News noted the group has been known to communicate with followers on WhatsApp, as well as other messaging apps.
Masood had convictions for violent crimes in Britain and spent time in prison. He also worked in Saudi Arabia teaching English for two years and traveled there again in 2015 on a visa designed for religious pilgrimages.