New York, 22 November 2023 (dpa/MIA) - A vehicle has exploded on the border between the US and Canada near Niagara Falls, the US Federal Bureau of Investigation (FBI) said on X on Wednesday, with media reports saying two occupants are dead.

The blast occurred at a border crossing between the US state of New York and the Canadian province of Ontario, New York Governor Kathy Hochul also wrote on X.

State police are working with the FBI Joint Terrorism Task Force "to monitor all points of entry to New York," Hochul said. She headed to the area to liaise with first responders.

The head of Ontario province, Doug Ford, said Canadian investigators were working with their US counterparts.

Three other border crossings with Canada in western New York were also initially closed, according to authorities. Security measures were increased at other crossings and some airports.

Apart from the two occupants, there are no other fatalities, the US broadcaster CNN reported, citing unnamed sources.

According to the report, the vehicle exploded at midday local time on the US side. The incident occurred in the immediate vicinity of the famous Rainbow Bridge.

US President Joe Biden has been briefed on the incident. He and his team are following developments closely, the White House announced.

Canadian Prime Minister Justin Trudeau said: "We are taking this extraordinarily seriously."

Some US media reported that the vehicle had approached the border crossing at high speed and was travelling in the wrong lane.

The FBI field office in the city of Buffalo said "this situation is very fluid, that's all we can say at this time."

Photographs of the border crossing showed debris and a large police presence.

US Congressman Mike Kelly of Pennsylvania was widely criticized on X for jumping to conclusions when authorities had not confirmed the nature of the explosion.

He wrote: "I’m incredibly alarmed by the attempted terror attack at the U.S.-Canada border. For months, I’ve warned about the surge of suspected terrorists entering through our Northern border. We must greatly enhance border security at ALL of our borders, including & especially the North."

Thursday marks the Thanksgiving holiday in the US, when family and friends traditionally get together. The day before is one of the busiest travel days of the year.