The Foreign Office (FCDO) has updated its advice for both Canada and the US following a car explosion at a border crossing close to Niagara Falls.
Two people were killed in the explosion and a border guard was injured at the Rainbow Bridge crossing yesterday.
The Rainbow Bridge spans the Niagara River gorge and connects the cities of Niagara Falls New York and Niagara Falls Ontario.
The FCDO said: “Ports of entry between the US and Canada may be closed and there may be long delays.
“You should follow advice of the local authorities.”
FBI Special Agent-in-Charge Matthew Miraglia and New York Governor Kathy Hochul told reporters that there was no indication of terrorism.
It is understood the car was being driven at high speed before it crashed, flew into the air and exploded on landing.
The driver is believed to have been from New York.
Investigations are continuing.