WhatsApp stopped working in what appeared to be a mystery outage.
The app was not sending or receiving messages and the independent website Down Detector detected a huge spike of outages, primarily in the UK and Europe.
The issues starting around 6pm GMT and appeared to last more than half an hour but full service has now been restored.
It was not just contained to Europe, with many users in South America, the Middle East and Asia unable to send or receive messages through the app.
The Facebook-owned app tends to be quite reliable, not often suffering major outages but as the app is used by more than one billion people around the world but any problems can affect hundreds of millions of users.
The app is the biggest messaging service globally and it is not currently known what caused the issue.
A spokesperson for Whatsapp said: “WhatsApp users around the world are unable to access the service. We apologize for the inconvenience and are working to fix the issue as soon as possible.”
The outage comes less than a month after Whatsapp rolled out a feature that allows you to "unsend" embarrassing messages.
“Starting today you can now delete messages you sent by mistake — whether to one person or an entire group," Whatsapp said in a blog post.
“Here's how it works: tap and hold on the message, choose ‘Delete’, and then ‘Delete for everyone’. You have seven minutes to delete the message after it's sent.
“This feature is rolling out for users around the world on the latest versions of iPhone, Android, Windows Phone as well as desktop. Both you and the message recipient must be using the latest version of WhatsApp for the message to be successfully deleted.”
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