WINONA, Minn. - Authorities believe there might be foul play in the disappearance of 26-year-old Madeline Jane Kingsbury, who was last seen on Friday.

In anews conference Wednesday morning, Winona Police Chief Tom Williams called Kingsbury's disappearance "involuntary" and "suspicious."

"We are all concerned for her safety," Williams said.

Kingsbury's family is offering a $50,000 reward for information leading to her whereabouts.

Police say Kingsbury was last seen Friday morning dropping her children off at day care shortly after 8 a.m., with the father of her children in her dark blue 2014 Chrysler Town and Country van.

She didn't show up for work at Mayo Clinic in Rochester or pick up her children later in the day.

Williams said the father of Kingsbury's children told police he left Kingsbury's home driving her van around 10 a.m., but didn't see her when he returned later that day.

Police searched the van and Kingsbury's home, where they found her phone, wallet, ID and a jacket she had worn earlier in the day.

Kingsbury is described as 5 feet 4 and 135 pounds with brown hair and hazel eyes.

A van matching the description of Kingsbury's vehicle was seen traveling on County Road 12 in Winona County, as well as Hwy. 43 in Winona and eastern Fillmore counties between 10 a.m. and 1 p.m. Friday.

Williams said there's no evidence Kingsbury left her home by foot or in another vehicle.

Winona police are working with local and state authorities to search for Kingsbury. Police are asking residents along County Road 12 and Hwy. 43 to search their properties and nearby trails, as well as check home surveillance cameras for any clues.

"If you have a camera, let law enforcement know," Williams said.