Donald Trump has blamed a lottery scheme for visa applicants for allowing the suspected New York terror attacker to enter the country.

The US President, citing unconfirmed reports about how Sayfullo Saipov, 29, entered the country, said: “The terrorist came into our country through what is called the ‘Diversity Visa Lottery Program,’ a Chuck Schumer beauty. I want merit based.

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

“‘Senator Chuck Schumer helping to import Europes problems’ said Col.Tony Shaffer. We will stop this craziness! @foxandfriends”.

Just minutes before Mr Trump sent his first tweet, Fox News’ Fox and Friends programme had posted a clip of Dan Bongino, a former Secret Service agent, railing against the lottery scheme to its Twitter account.

The visa lottery makes available 55,000 immigrant visas, known as green cards, every year for people from countries with low rates of migration to the US.

Mr Saipov, an Uzbek national, entered the US legally in 2010. Officials have not said whether he came via the lottery scheme.

He was arrested after a truck ploughed through pedestrians and cyclists near the World Trade Centre in Manhattan on Tuesday, and then crashed into a schoolbus.

The rampage left eight dead and 11 seriously injured.

New York Truck attack Show all 6 1 /6 New York Truck attack New York Truck attack Investigators inspect the truck following the attack Investigators inspect a truck following a shooting incident in New York on 31 October 2017. Several people were killed and numerous others injured in New York on Tuesday when a suspect plowed a vehicle into a bike and pedestrian path in Lower Manhattan, and struck another vehicle on Halloween, police said. A suspect exited the vehicle holding up fake guns, before being shot by police and taken into custody, officers said. The motive was not immediately apparent. Getty New York Truck attack A paramedic looks at a body along the bike path A paramedic looks at a body covered under a white sheet along the bike path 31 October 2017, in New York. A motorist drove onto a busy bicycle path near the World Trade Center memorial and struck several people Tuesday, police and witnesses said. AP Photo/Bebeto Matthews New York Truck attack The truck driver collided with a school bus Authorities respond near a damaged school bus Tuesday, 31 October 2017, in New York. A motorist drove onto a busy bicycle path near the World Trade Center memorial and struck several people, police and witnesses said. Two adults and two children were on the bus at the time. AP Photo/Bebeto Matthews New York Truck attack A young girl reacts to the scene A young girl reacts as police officers secure an area following a shooting incident in New York on 31 October 2017. Several people were killed and numerous others injured in New York on Tuesday after a vehicle plowed into a pedestrian and bike path in Lower Manhattan, police said. 'The vehicle struck multiple people on the path,' police tweeted. 'The vehicle continued south striking another vehicle. The suspect exited the vehicle displaying imitation firearms & was shot by NYPD.' DON EMMERT/AFP/Getty Images New York Truck attack Police officers arrive at the scene Police officers arrive at the scene following a shooting incident in New York on 31 October 2017. Multiple people were hurt in downtown Manhattan, US media reported after police confirmed that they were responding to reports of a shooting. Police said they had mobilized to the scene in Lower Manhattan and that one person was in custody, giving no further details. DON EMMERT/AFP/Getty Images New York Truck attack Emergency personnel respond to truck attack in lower Manhattan Emergency personal respond after reports of multiple people hit by a truck after it plowed through a bike path in lower Manhattan on 31 October 2017 in New York City. According to reports up to six people may have been killed. Kena Betancur/Getty Images

Uzbekistan said it was ready to do everything it could to help investigate.

President Shavkat Mirziyoyev made the offer of help in a letter of condolence to Mr Trump in which he condemned the attack as “extremely brutal” and said there could be no justification for such violence.

The attack is a challenge for Mr Mirziyoyev who assumed office at the end of 2016 and is trying to slowly open up his country after decades of authoritarian rule.

It also shines an uncomfortable light on Islamist militancy in the wider region which has supplied Islamic State in Syria and Iraq with thousands of fighters.