All they really know is that the place was full of obviously Roman artifacts. Whether that means it was a cemetery for Roman expatriates or for natives who just happened to have loads of Roman stuff is a matter of interpretation...

Here's an article about it in one of the bigger Danish newspapers, unfortunately in Danish:
http://politiken.dk/videnskab/article401616.ece

Apparently there are about 30 graves overall, one of them for a nobleman.
They found a gold ring, some sort of clothes pin of silver (which according to them is otherwise usually only found much further south during that period) and what the article calls a "circus cup" - the first image is of a copy of one - in his grave. They also found 58 glass pieces used for a game like checkers.
The nobleman's body is well preserved, so they hope to find out whether he was of native ethnicity or not - and perhaps find a coin in the mouth for the ferryman.

The 30 other graves are from the generations after the nobleman.