The Czech cyber security watchdog warned on Wednesday against using TikTok, joining a growing number of Western agencies alleging the Chinese-owned social media app poses a security risk. The NUKIB agency recommended that TikTok should not be installed on phones whose users access critical and other significant infrastructure. “The Agency is concerned about potential security threat stemming from the use of TikTok primarily due to the amount of user data that is collected by the app as well as the way the data is handled.” NUKIB said. “Such large-scale data collection is concerning due to the legal and political environment of the People’s Republic of China (PRC), given that ByteDance, the developer and administrator of TikTok, falls under the legal jurisdiction of the PRC.” NUKIB also recommended politicians and officials to avoid using TikTok, and said the wider public should consider whether to use the app as well, especially for sharing content. TikTok did not immediately respond to a request for comment. ByteDance has said previously that concerns about the app are fuelled by misinformation, and has denied using it for spying. Beijing has also repeatedly denied having any intention to use the app for espionage. Several countries have taken steps to limit TikTok’s use. The United States last month set a 30-day deadline to purge the app from federal devices and systems. The European Parliament, the European Commission and the EU Council have banned TikTok from staff phones.