Prosecutors on Tuesday were preparing felony charges against a driver in connection with the death of a young mother who was struck while on her bicycle Monday and pulling her two little daughters behind in a trailer on a southwestern Minnesota highway.

Charges that include criminal vehicular homicide are pending against Christopher M. Weber, 25, of Brandon, S.D., prosecutors said.

The crash occurred about 11:30 a.m. Monday on Hwy. 270, killing Andrea L. Boeve, 33, just north of the family’s hometown of Steen, Minn., according to the State Patrol.

Her daughters, 4-year-old Claire and 1-year-old Mallorie, were hospitalized in Luverne, Minn., with injuries that were not serious, prosecutors said.

Evidence suggests Weber was using a cellphone, but prosecutors said details have not yet been revealed because the complaint hasn’t been signed by a judge in Rock County District Court.

If the complaint is accepted by the court, authorities anticipate Weber will make his initial court appearance on Wednesday, the prosecutors said.

Weber also is expected to be charged with criminal vehicular operation because of the children’s injuries.

Boeve was obeying Minnesota law, which calls for bicyclists to ride in the same direction as motorized traffic. She also was wearing a helmet, although it is not legally required.

The bicycle was heading east on Hwy. 270 in Rock County, when it was hit from behind by a pickup.

Weber, who was not hurt, was arrested on suspicion of criminal vehicular homicide or operation.

The patrol has been investigating whether that man was distracted by his cellphone before he crossed the solid white line that separates the lane and the paved shoulder, and then hit the bicycle.

Staff writer Joy Powell contributed to this report.