ANKARA, Turkey (AP) — Turkey’s competition watchdog on Monday launched an investigation into Facebook and WhatsApp over the messaging application’s changes to its data-sharing rules.

The Competition Board also said in a statement that it has ordered a suspension of WhatsApp’s new data collection rules in Turkey.

The move came after the messaging application said it was updating its terms of service and privacy rules as of Feb. 8, forcing users to agree to sharing more of their data with Facebook, which owns WhatsApp. The company says the changes are related to business transactions and that private messages wouldn’t be affected.

Turkish WhatsApp users, concerned about that the possible sharing of their personal information, began downloading alternative messaging applications such as Signal or Telegram. Many chose to close down their WhatsApp accounts even though the messaging app assured that the content of messages would remain encrypted.

The Competition Board said its investigation would focus on whether Facebook and WhatsApp were in violation of Article 6 of Turkey’s competition laws, which bar companies from “abusing their dominant positions.”

President Recep Tayyip Erdogan’s office and Turkey’s Defense Ministry announced over the weekend that they were ceasing using WhatsApp to communicate with journalists and asked them to download the Turkish messaging application, Bip, which was developed by mobile phone operator Turkcell.