2- Judge the situation fairly. Find the original source of information and ask directly if possible and applicable.
3- Discuss the matter with two to three person. If all of them have a different story then most likely the original story is lost or it is completely false. Consider the parts which are common in all stories. This will help extract the original components of the news.
4- Don't get too much engaged in rumors however a serious advice is not to ignore the rumors completely. The news might be genuine, hence you must consider the corrective and preventive necessary measures else you may face serious consequences. You must be logical and analytical in your evaluation of the rumor.