An American soldier who sought refuge in Canada after becoming disillusioned with the Iraq war has been arrested after turning herself over to the United States.

Kimberly Rivera complied with a deportation order and presented herself at the border at Gananoque, Ont., on Thursday.

The War Resisters Support Campaign — which issued multiple warnings that Ms. Rivera would likely face a court martial and jail time on her return — said the mother of four was immediately arrested, detained and transferred to U.S. military custody.

“Kimberly now awaits punishment for refusing to return to Iraq, a conflict which Kimberly and Canada determined was wrong,” the group said in a statement.

Ms. Rivera was being held in Fort Drum, N.Y., some 360 kilometres from Toronto, and was waiting to be transferred to a different military facility where she faces punishment for being absent from her unit, the group said.

The 30-year-old’s husband and her children — two of whom were born in Canada — crossed the border separately on Thursday.

“She didn’t want her children to see her arrested by the military,” said spokesman Ken Marciniec.