Public transport between Muscat and Duqm

Hope somebody could tell me how to reach Duqm from Muscat and vice versa. I have done some research on the internet, but still lacking the information about existence of public transport between the two mentioned locations.

I plan to visit Duqm within the two months from today, so this is undoubtedly important information. Without it, it is impossible for me to plan anything from the very beginning because I will have limited days to accomplish everything.

Thanks.