Six people from two families -- one of Romanian descent with Canadian passports, the other from India -- were found dead in a marsh near the Canada-US border after trying to cross illegally into the United States, police said confirmed on Friday.

Their bodies were discovered late Thursday near a capsized boat belonging to a missing man from the Akwesasne Mohawk community, local deputy police chief Lee-Ann O'Brien told a news conference.

"The six individuals are believed to be from two families, one of Romanian descent and the other believed to be citizens of India," O'Brien said, adding that they include five adults and one child under the age of three.

"All are believed to have been attempting illegal entry into the US from Canada," she said.

O'Brien added that a second infant whose passport was recovered from one of the bodies appears to also be missing and police dive teams were continuing to search.

The capsized boat was described as "very small" for poor weather conditions including rain, sleet, and strong wind.

"It was not a good time to be out on the water," O'Brien said.

The first body was found during an aerial search of the area. Authorities are waiting on autopsy as well as toxicology test results to determine the cause of death.

Prime Minister Justin Trudeau, speaking to reporters, said, "Our hearts go out to the families of the individuals who perished. This is a heartbreaking situation, particularly given the young child that was among them."

O'Brien highlighted a recent "increase in people passing through Akwesasne gaining entry into the US," with 48 crossings since the start of the year.

Once landing on the US side, they are typically picked up on shore and transported by vehicle into New York State, she said.

Two other people have been found dead near the border in recent months while trying to cross illegally into the United States from Canada. 

The two countries struck a deal on managing the growing issue of undocumented migration on their lengthy border during US President Joe Biden's visit to Ottawa last week.

The arrangement will see undocumented asylum seekers crossing from the United States into Canada turned back, while Canada will simultaneously expand the pathway for legal entry.

The plan -- similar to a crackdown on the much more heavily used US-Mexican border -- has been criticized by migrants' rights activists. Biden and Trudeau are both under political pressure to relieve their badly strained immigration systems.

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