Ontario Provincial Police say four people have been arrested and charged in connection with an apparent human smuggling scheme after a vehicle bound for the United States was found to have several people hidden inside of it.

Police said the vehicle was stopped in Cornwall, Ont. on Tuesday, heading toward the Canada-U.S. border. Officers found eight people hidden in the back of the vehicle. The driver and passenger of the vehicle were arrested. Two more suspects were arrested in two other vehicles following further investigation.

Chris Edwards, 58, of Akwesasne, George Tooker, 54, of Akwesasne, Ngoc Dung Le, 52, of Brossard, Que. and Huu Huan Nguyen, 43, of Anjou, Que. have each been charged with conspiracy to violate U.S. law.

The accused were released from custody with a Feb. 25 court date in Cornwall.

We will continue to identify, investigate, dismantle and prosecute individuals who attempt to exploit our nations borders, said OPP Commissioner Thomas Carrique in a news release Wednesday. Maintaining the integrity of our borders is of utmost importance and we will continue to collaborate with our partners provincially, nationally and internationally.

Police also arrested the eight people who were hidden in the first vehicle and said charges could be laid, if applicable.

The OPP said the investigation involved the Canada-U.S. Border Enforcement Security Task Force, and officers from the Canada Border Services Agency, the RCMP, the Akwesasne Mohawk Police Service, and the U.S. Department of Homeland Security.

These arrests are another example of a decades-long partnership between multiple law enforcement and border protection agencies. By working together, we are enhancing our efforts to combat human smuggling and ensure the safety and security of Canadians and our borders, said RCMP Assistant Commissioner Matt Peggs.

The news comes amid tensions in the relationship between Canada and the United States, after U.S. president-elect Donald Trump threatened to impose steep tariffs on Canadian imports unless Canada stops the flow of illegal drugs and migrants over the border.

He has also repeatedly commented about annexing Canada, possibly through the use of economic force . Canadian leaders have rebuffed his comments, with Prime Minister Justin Trudeau saying there is not a snowballs chance in Hell that Canada would become part of the United States.

The federal government announced new border measures  in December, but Parliament is currently prorogued until March 24, after Prime Minister Justin Trudeau announced his intention to resign following a Liberal leadership race.