(Tibet) -- A team of scientists says they've uncovered some ancient viruses from a Tibetan glacier.  

The previously unknown viruses are believed to date back to 15-thousand years ago and are unlike anything scientists have cataloged before, according to a study that came out in the journal Microbiome this week.  

Ohio State University climate scientists and microbiologists got the ice cores from the summit of an ice cap in western China back in 2015.  

From the ice, the team found 33 viruses. At least 28 were unknown before now and survived because they were frozen.