Mother, 3 daughters found shot to death in Missouri

(CBS/AP) DE SOTO, Mo. -- Authorities say they suspect a mother shot and killed her three young daughters before killing herself outside her estranged boyfriend's home in rural eastern Missouri.

Jefferson County Sheriff Glenn Boyer says all four were found shot in the head early Thursday at a home near De Soto, about 45 miles south of St. Louis. The victims' names weren't immediately released.

The 32-year-old woman was found dead on steps leading to the porch of the home of her estranged boyfriend. The girls, ages 1, 10 and 11, were found inside a van in the driveway.

Boyer says an email sent by the mother to relatives and her ex-boyfriend led investigators to believe she killed the children, then herself. Police say a newly purchased 12-gauge shotgun was found near the woman.