LISBON, April 5 (Reuters) - A Portugal-based European consumer protection group has sued short-video app TikTok for allegedly allowing children aged under 13 to sign up for an account without parental consent and failing to implement measures to protect them. Amid growing security concerns that China could use the Beijing-based company, owned by ByteDance Ltd, to harvest users' data, Australia, the United States, France and other Western countries have also lately banned TikTok from government devices. See here for a complete list of exchanges and delays