Users around the globe reported that the popular messaging app WhatsApp had stopped working on Tuesday.
Reports showed outages across Europe and in the US, Mexico and South America.
Users reported they were unable to send or receive messages, or only see a spinning wheel that says "connecting". Several mobile communications companies told customers that technicians were looking into the outages.
The mobile messaging program for iPhone, Android phones and other devices allows users to send and receive messages, photos and other messages as an international alternative to texting.
An outage in March left WhatsApp users— as well as users on Instagram and Facebook, which owns both companies — in the dark for nearly a day, among one of the largest outages in several years.
More than 500 million people use the app daily.
Starting in February 2020, the app will stop working for some users as it begins to remove its service from older model phones and software, which could potentially bump millions of users from the app.
iPhones running iOS 8 or older and Android devices running 2.3.7 or older will no longer be supported.
“For the best experience, we recommend you use the latest version of iOS available for your phone,” WhatsApp said in a blog post.
The app will also stop working for all Windows phones beginning 31 December 2019.
On Monday, Facebook — which acquired the app in 2014 — told the US Justice Department that it doesn't plan to weaken its end-to-end encryption despite pressure from law enforcement in several countries.
WhatsApp head Will Cathcart and Facebook Messenger's Stan Chudnivsky said it would be impossible for the companies to create a "backdoor for one purpose and not expect others to try and open it."
"People’s private messages would be less secure and the real winners would be anyone seeking to take advantage of that weakened security," their statement said. "That is not something we are prepared to do.”