Small Flys connected at Tail

I am making some supersoil. I just opened my trash can to find hundreds of small bugs connected at their rear running around in the bin. They appear to have wings, and are about 1/32 of an inch long. They also look like they can run in either direction.[HR][/HR][HR][/HR] I have had many fungus gnats over the years but do not think that is what these are as I have never seen them before. They appear to be some sort of fly that is breeding. Does anyone know what these are, and if they are a problem. I really don't want to bring these indoors. Any input would be appreciated.