9:45 AM PT -- The suspect accused of shooting three Palestinian men has pleaded not guilty to three counts of attempted murder in the second degree.

Police released a booking photo of Jason Eaton. He's being held without bail.

A Vermont man is now in custody after cops claim he shot 3 Palestinian college students in what might be a possible hate crime ... this as tensions continue to rise in the Middle East.

48-year-old Jason Eaton was arrested Sunday near Burlington ... the site of the Saturday night shooting when 3 young men of Palestinian descent were fired upon on the street as they were walking and speaking Arabic and heading to a family dinner.

They've since been identified as Hisham Awartani, Tahseen Ahmad and Kinnan Abdalhamid ... all of whom attend different universities in New England, including Brown.

At least 2 of them were also wearing traditional Keffiyeh scarves ... a garment often worn in Muslim countries. Because of this and the fact they were seemingly attacked without provocation, U.S. officials are saying this might be a hate crime, and the feds are investigating whether that's the case or not.

As for Eaton ... it's unclear what charges, exactly, he's facing at this point -- but he's due to be arraigned Monday. When announcing his arrest, law enforcement cited "three incidents of aggravated assault."