WINONA, Minn. -- A Minnesota man has been arrested in connection with the disappearance of his ex-girlfriend, after a deputy found human remains in a rural area.

Madeline Kingsbury, whose 27th birthday was June 1, was last seen on March 31 after dropping off her two young children at daycare in Winona, a southern Minnesota town of about 26,000 residents. Police said a deputy found human remains Wednesday afternoon in brush along a highway near Mabel, about 46 miles (74 kilometers) south of Winona.

The Southern Minnesota Regional Medical Examiner's Office is working to identify the remains, but a news release from Winona police said the body was discovered “using information generated during the Madeline Kingsbury investigation.”

Later Wednesday, police arrested a 29-year-old man who is the father of Kingsbury's two children. Jail logs show that he was being held on suspicion of second-degree murder, the Minneapolis Star-Tribune reported. As of Thursday morning, charges have not been filed.

Kingsbury's children, ages 2 and 5, have been in the custody of her parents since she went missing.

Police said in a Facebook post that a news conference was expected Thursday.