Wrongful termination

I was recently terminated after a protracted situation with a major federal security contractor. The story goes like this:

About a month ago, I was approached by two supervisors who informed me that there was "a rumor" going about that I had pointed a firearm at a coworker while on duty. I told them that the rumor was false and in questioning them about the situation, they told me that the individual who I supposedly threatened had denied that the event had occured. I was also told that the allegation would be dropped by these supervisors.

Three weeks later I was told by one of the same supervisors to write a written statement concerning the allegation. I did so and retained a copy. I asked why I needed to write this statement and my supervisor said "I don't know."

The next day a supervisor from the company to which my company was contracted spoke to our team and in a very threatening way stated that the allegation was still under investigation and that she expected to terminate someone "if we get the information we need."

The next week I was informed that an allegation was made to a special safety oversight organization and that I would be questioned by independent investigators. These investigators told me after my interview that they expected to dismiss the allegation the next day after they spoke to some other employees.

The next day I was suspended. four days later I was terminated over the telephone by a corporate manager not affiliated with our facility.

I believe that I was terminated after pressure was put on my company by the contract holder. I was told that all allegations against me were made either through rumors or by an anonymous allegation.

What legal recourse do I have?