Neeraj Arora(L) attends the 2019 Breakthrough Prize at NASA Ames Research Center on November 4, 2018 in Mountain View, California

Neeraj Arora, WhatsApp’s chief business officer, said he is leaving the popular messaging service, joining a stream of top executives who have departed Facebook and its group companies in the past year.

Arora, an IIT- Delhi alumnus and the number four in the company, was being touted to take over as WhatsApp CEO earlier this year, however, the role of global head of the company was given to Chris Daniels.

Arora had been with WhatsApp since 2011 and through Facebook’s USD 19 billion acquisition of the messaging company in 2014. His exit comes seven months after WhatsApp co-founder Jan Koum left the company.

“It is hard to believe that it has been seven years since Jan (Koum) and Brian (Acton) got me onboard at WhatsApp, and it has been one hell of a ride! It is time to move on, but I cannot be more proud of how WhatsApp continues to touch people in so many different ways every day,” Arora said in a Facebook post on Monday.

“I am confident that WhatsApp will continue to be the simple, secure and trusted communication product for years to come,” he wrote.

Arora’s departure comes at a challenging time for WhatsApp, which has been dealing with the growing international problem of users spreading misinformation to large groups of people. This year WhatsApp deployed campaigns in top markets like India and Brazil to educate users and help them avoid sending around false information, CNBC said.

In addition to the recent departure of top WhatsApp executives, Facebook has also lost Instagram co-founders Kevin Systrom and Mike Krieger and Oculus co-founder Brendan Iribe in recent months. Alex Stamos, who was Facebook’s chief security officer, left in August.