Video Imports as an Audio File Only! Please Advise.

Hello :)
I've worked with Premiere for years, and never once has this happened. I'm hoping someone will have an answer or suggestion for me in this dilema.

I was given a few video files which were filmed with a Vivitar HD 1080.
One of the files was a .mov, and the others were .avi

So, the mov imported just fine. However, the .avi files are importing as audio files ONLY. I have spent hours trying to figure this out, even trying to convert the .avi's to .mov's. That doesn't work either. They are still importing as audio files. I know the video exists, because I can open it in various media players, so the question is, Why oh WHY is Premiere importing it as audio only?

Please help ....

Thanks in advance!

Lisa