As of my last update in early 2023, I do not have access to real-time data or t

As of my last update in early 2023, I do not have access to real-time data or the ability to provide current news updates. Therefore, I cannot confirm the accuracy of the statement that the death toll in a Moscow terror attack has risen to 143, as reported by RT. For the most recent and accurate information on this subject, please consult the latest reports from reliable news sources or official statements from Russian authorities.