US President Donald Trump has raised the prospect of sending the man accused of the New York terror attack to prison at the notorious Guantánamo Bay detention centre in Cuba.

Eight people were killed and a dozen injured when a man drove a rented pickup truck down a busy bicycle path in central New York on Wednesday.

It was the worst terror attack in New York since the September 11, 2001 Twin Towers tragedy.

Sayfullo Saipov, a 29-year-old Uzbek-born legal US immigrant, appeared in the New York federal courthouse on Thursday handcuffed and with his feet shackled.

Federal prosecutors say he was “consumed by hate and a twisted ideology” when he attacked.

He is charged with providing material support to the Islamic State terror group, and violence and destruction of motor vehicles. His lawyers haven’t responded to calls seeking comment.  

Prosecutors they say he had been planning the attack for months.

Mr Trump earlier told reporters he would consider Saipov him to the infamous Cuban jail, established in 2002 to house “extraordinarily dangerous” people but where no-one arrested on US soil has ever been held.

“Send him to Gitmo, I would certainly consider that, yes,” the President said in answer to reporters’ questions in Washington.

Mr Trump also announced he would terminate the popular US green card lottery system, which awards permanent visas to around 50,000 applicants a year from countries typically underrepresented in US immigration.

Meanwhile, it emerged today that five of the eight people killed in yesterday’s attack were former classmates celebrating their 30-year high school reunion.

The childhood friends, who were now in the 40s, had planned their reunion visit to New York over the past 12 months and had only arrived in the city 48 hours earlier, The New York Times reported.

The men all came from Rosario, Argentina’s third largest city.

The childhood friends planned their trip for years. Photo: Twitter

After crashing into a school bus, Saipov is alleged to have jumped out with a pellet gun and paintball gun and shouted “Allahu Akbar,” Arabic for “God is great”.

He was brought down by NYPD officer, Ryan Nash, who fired nine shots at Saipov, hitting him in the abdomen.

Investigators say they found a handwritten note in the rented truck indicating allegiance to Islamic State.

The New York Times reported Wednesday that Saipov came to the United States in 2010 and was a legal permanent resident. He drew concerns at a mosque in Tampa, Florida, that he attended before moving to New Jersey.

The paper quoted “Abdula”, a preacher at the mosque, as saying he tried to steer Saipov away from extremism.

“I used to tell him, ‘Hey, you are too much emotional,’” Abdula said, adding: “I never thought that he would go to this extreme.”

Saipov moved to New Jersey in March to be closer to his wife’s family. She was due to have their third child, his first son, who was born sometime in the summer, probably July, Abdula said.

“He was hoping to have a son for a long time,” Abdula told The Times. “I would never think that he would do this kind of thing.”

Mr Trump wasted no time in trying to score political points off the attack.

Less than 24 hours after the tragedy he took to Twitter blaming the Democrats and specifically their leader in the Senate, Chuck Schumer.

Mr Trump tweeted early Wednesday: “The terrorist came into our country through what is called the “Diversity Visa Lottery Program,” a Chuck Schumer beauty. I want merit based.”

The terrorist came into our country through what is called the "Diversity Visa Lottery Program," a Chuck Schumer beauty. I want merit based.

— Donald J. Trump (@realDonaldTrump) November 1, 2017

We are fighting hard for Merit Based immigration, no more Democrat Lottery Systems. We must get MUCH tougher (and smarter). @foxandfriends

— Donald J. Trump (@realDonaldTrump) November 1, 2017

His preparedness to weigh in and play politics was in contrast to the White House’s stance last month immediately after the Las Vegas massacre in which 58 people died and hundreds more were injured at the hands of a lone gunman.

Then it was “too early” to discuss gun control or engage in political debate but today it appeared there were no such niceties to be observed. Trump’s tweet brought a swift condemnation from Senator Schumer.

“President Trump, instead of politicizing and dividing America, which he always seems to do at times of national tragedy, should be focusing on the real solution — antiterrorism funding — which he proposed cutting in his most recent budget,” Mr. Schumer said in a statement.

Hours later, in response to reporters questions, President Trump said he would work to abolish the program that allowed Saipov into the United States.