Canadian Prime Minister Justin Trudeau deleted a tweet containing false information about mass death sentences in Iran, following a viral social media campaign that circulated the fake news.

Celebrity and users also shared a photo on Instagram showing a woman holding an Iranian flag with a caption saying "Iran sentences 15,000 protesters to death - as a 'hard lesson' for all rebels."

Instagram has since labeled the post as "misinformation" and said "Independent fact-checkers say this information has no basis in reality." Celebrities who posted the now-deleted post include actresses Sophie Turner and Viola Davis.

Also, Trudeau tweeted late Monday that Canada condemns "the barbaric decision of the Iranian regime to impose the death penalty on nearly 15,000 protesters." The tweet was up for 12 hours before being removed.

A Canadian government spokesperson also told CNN: "The post was reported based on an initial report that was incomplete and lacked the necessary context. For this reason, it has since been deleted." The spokesperson added: "It was based on reports of serious concerns raised by international human rights advocates warning of potential future penalties, including the death penalty, for thousands of Iranian protesters already arrested by the regime."

Similarly, Iranian legislators are demanding that the judiciary in the country "not be lenient" with protesters, but so far the judiciary has officially sentenced only one person to death this week. However, the United Nations warned last week that others are at risk of receiving similar sentences. UN experts said last week: "As the crackdown on protests continues, many indictments for charges punishable by death sentences and execution judgments may soon be issued."

At least 2,000 people have been accused of alleged involvement in the protests that swept across the country over the killing of 22-year-old Mahsa Amini, the largest opposition demonstration in years. Trials are public and have lasted for more than two weeks. According to the Islamic Republic News Agency, sentences can be appealed.

In addition, human rights organizations said at least 326 people have been killed in the protests. CNN cannot independently verify the numbers of arrests and deaths and many of the death reports, due to the Iranian government's repression of media, internet, and transparency.