TikTok’s efforts to stop children using the app and protect their personal data have been inadequate, a Canadian investigation has found.

Hundreds of thousands of children in the country use TikTok each year despite the firm saying it is not intended for people under the age of 13, according to the findings.

The investigation also found TikTok had collected sensitive personal information from “a large number” of Canadian children and used it for online marketing and content targeting.

TikTok told the BBC that it will introduce a number of measures to “strengthen our platform for Canadians” although it disputes some of the findings.

The investigation was carried out by Canada’s privacy commissioner, Philippe Dufresne, and privacy protection officials.

At a news conference to announce the findings, Mr Dufresne said the hugely popular short-video platform collects “vast” amounts of information from its users, including children.

“This data is being used to target the content and ads that users see, which can have harmful impacts, particularly on youth,” he added.

Mr Dufresne said that in response to the investigation TikTok had agreed to enhance measures to stop children using the platform and to more clearly indicate how their data could be used.

In statement a TikTok spokesperson said it welcomed the investigation and that Canadian officials had “agreed to a number of our proposals to further strengthen our platform”.

“While we disagree with some of the findings, we remain committed to maintaining strong transparency and privacy practices,” they added.

The BBC has asked the company to specify which findings it disagreed with.

The Canadian investigation is the latest move by governments around the world to scrutinise TikTok’s impact on users as well as national security concerns over the Chinese-owned app.

The company and Beijing have repeatedly denied such allegations.

In the US, President Donald Trump has been negotiating with his Chinese counterpart Xi Jinping about a deal that could see TikTok’s US operations being taken over by a group of American companies.

In 2023, staff working at the European Commission were ordered to remove the TikTok app from their phones and corporate devices.

The commission said it was implementing the measure to “protect data and increase cybersecurity”.