The uncle of an Irish-Palestinian-US citizen who was shot in Vermont on Saturday has said his nephew was hit in the spine by a bullet and faced a long period in hospital.

Hisham Awartani was one of three 20-year-old university students of Palestinian descent who were wounded in the shooting in the north-eastern US city of Burlington on Saturday.

Mr Awartani is a second-year student at Brown University in Providence, Rhode Island.

His great-uncle Marwan Awartani, a former Palestinian Authority education minister, told the New York Times that a bullet had struck his spinal cord and that he had lost feeling in the lower part of his body.

In a statement, Burlington police said that the suspected shooter carried out the attack on a street near the University of Vermont and then ran away.

The incident occurred amid high tensions, and occasional violence, on college campuses and elsewhere in the United States over the Israel-Hamas war.

Not guilty plea

The suspected shooter today pleaded not guilty to three counts of attempted second-degree murder and was ordered by a judge to be held without bond.

The suspect, Jason J. Eaton, 48, appeared at an arraignment at the Chittenden County Criminal Court in Burlington via a remote video feed from the county jail, where he has been held since his arrest yesterday.

The attack is under investigation by local and federal authorities as a suspected hate-motivated crime.

At the time of the shooting, two of the victims were wearing a keffiyeh, the traditional black-and-white checkered head scarf commonly worn in the Middle East, police said.

"Although we do not yet have evidence to support a hate crime enhancement, I do want to be clear that there is no question that this was a hateful act," said Sarah Fair George, state's attorney for Chittenden County, during a briefing today.

Dressed in an orange jumpsuit at the three-minute hearing, Mr Eaton responded "yes, sir" when asked by the judge if he understood the charges against him.

Police said the suspect had legally acquired the gun used in the shooting a few months ago.

The victims were reported to have been speaking Arabic when attacked, according to the Institute for Middle East Understanding, a nonprofit pro-Palestinian advocacy organisation.

It also said the assailant opened fire on the three men after he began to shout at and harass them.

Police say he fired four shots without saying a word.

Community 'deeply shaken'

A statement from Brown University President Christina H Paxson to the university community yesterday evening said that they were "very relieved and grateful to learn that he (Hisham Awartani) is expected to survive his injuries."

She said the family of Mr Awartani gave permission to share his circumstances and that he and his two friends "may have been targeted because of their Arab ancestry and identity".

"There are not enough words to express the deep anguish I feel for Hisham, his parents and family members, and his friends," she said.

"I know that this heinous and despicable act of violence - this latest evidence of anti-Arab and anti-Palestinian discrimination and hate spiralling across this country and around the world - will leave many in our community deeply shaken.

"We know it will heighten concerns about personal safety and security for Palestinian and Arab members of our community," she added.

The University is holding a vigil on Monday afternoon to "condemn anti-Arab and anti-Palestinian discrimination and acts of violence and hate, and express care and empathy for one another," she said.

President Biden 'horrified'

The Irish Department of Foreign Affairs said it has not been contacted in relation to the incident, but that the Consulate-General of Ireland in Boston is aware of the case and is ready to provide consular assistance if requested.

The DFA said it does not comment on individual cases.

The White House said President Joe Biden was horrified by the shooting.

"There is absolutely, absolutely no place for violence or hate in America," White House spokesperson Karine Jean-Pierre told reporters at a news briefing.

The other two victims were identified as Kinnan Abdel Hamid, a student at Haverford College in Pennsylvania; and Tahseen Ahmed, who attends Trinity College in Connecticut.

All three students are graduates of the Ramallah Friends School, a private Quaker secondary school in the Israeli-occupied West Bank, the families said.

Two of the students were visiting the home of the third student's family in Burlington for the Thanksgiving holiday.

Additional reporting: Gail Conway, AFP