The directive was sent more than three weeks ago by inspectors from the HCMC Department of Information and Communications, ordering two domains, Zalo.vn and Zalo.me to be suspended from July 19 until further notice.

Vietnamese tech firm VNG Corporation, which owns the domains, has been fined an unknown amount for its violations. As of publishing, both Zalo.vn and Zalo.me were still functional.

This is not the first time VNG has been fined for running social media services without approval. It was fined for the same violation last year by the department.

Nguyen Duc Tho, chief inspector of the department, said the company paid the fine then, and has been given time to provide necessary documents for approval, but has never done so. Other social media service providers in Vietnam all have obtained approvals before going public, Tho said.

Zalo Group, part of VNG, has said multiple times that Zalo is simply an over-the-top (OTT) application.

Since Vietnam has no policies regarding the management of OTT apps and Zalo’s operation is too similar to a social media service, approval was necessary, said Tho.

VnExpress could not reach Zalo representatives for further information. But a source said VNG was planning to sue the inspectors of the information department.

VNG Corporation and Zalo Group have yet to comment on the issue.

Zalo began as an application for calling and texting on the Internet, but is tied to personal phone numbers. Its functions later expanded, including personal profiles and the uploading of images and videos.

It has grown to be a popular messenger app, garnering more than 100 million users globally after seven years.