NOYES, Minn. A woman who may have been trying to reach Canada on foot from the United States probably froze to death in a remote part of northwestern Minnesota, authorities said.

The body of 57-year-old Mavis Otuteye, who authorities believe was a citizen of Ghana in western Africa, was found Friday in a field a half-mile from the Canadian border near the tiny town of Noyes, according to the Kittson County Sheriff’s Office.

Otuteye was reported missing a day earlier and was likely headed to Canada on foot to try to reunite with her daughter, Chief Deputy Matt Vig told WDAZ-TV. He said Otuteye had been living in Delaware for the past several years.

Final autopsy results are pending, but Vig said the preliminary results indicate she died of hypothermia. The officer said part of her body was in a shallow pool of water in a drainage ditch.

“The temperatures that night were in the 40s,” Vig told the Grand Forks, North Dakota, television station. “Just tough weather for her to make that journey.”

Otuteye’s immigration status in the US was not immediately clear. Vig did not immediately return a call from The Associated Press on Wednesday. Kris Grogan, a regional spokesman for US Customs and Border Protection, said his agency was awaiting final confirmation of her identity before releasing more information.

There’s been a surge in immigrants trying to illegally cross the US border into Canada on foot from Minnesota and North Dakota since Donald Trump became president. Officials say most of the immigrants have been natives of Somalia, which was one of the countries named in Trump’s attempted travel ban, but they’ve also come from Ghana, Djibouti, Nigeria and Burundi.

Many of them risked brutal winter weather to avoid border posts because official Canadian entry points turn back asylum seekers arriving from countries considered safe, such as the US. But that policy doesn’t apply to people who reach Canadian soil first, resulting in many people crossing fields and ditches to avoid the official checkpoints.

The most recent Royal Canadian Mounted Police figures show that 859 people were stopped between official border points in April. So far this year, there have been 1,993 interceptions in Quebec, 477 in Manitoba and 233 in British Columbia.

Otuteye’s death remains under investigation by Kittson County sheriff’s officials and the Minnesota Bureau of Criminal Apprehension.