Social media giant Meta Platforms, formerly known as Facebook, says there has been a surge in cyberattacks including social media disinformation since the start of the Russian invasion of Ukraine.

The US tech firm issued its quarterly adversarial threat report on Thursday.

Meta said in the report that, as an example, a party allegedly linked to the Belarusian government posted fake news in Polish and English "about Ukrainian troops surrendering without a fight and the nation's leaders fleeing the country."

The firm also said it has removed tens of thousands of accounts that were engaged in fraud since the military operation began.

Meta said some of them tried to trick people watching videos "so they can try making money by either driving people to off-platform ad-filled websites or selling them merchandise."

The firm is calling on people to strengthen the security of their online accounts by such means as using a VPN service that enables them to ensure an encrypted connection.