It was posted in haste to go ahead of competition or Londra che esce con sito youtube libero was just a mere desire to share the information without validation. Getting the side of the affected party to balance the delivery of the news is not validation. A journalist has to investigate in order for his facts to be valid. When a second source tells you the information is not true, then go back to the first source who broke the news to you and re- validate.
If the first source can prove the information he relayed to you is true, then ask again the second source for rebuttal.