A Columbus woman and her 12-year-old son are dead following a crash on a wet city street.

The crash happened around 9 p.m. Wednesday when 37-year-old Maria Diaz lost control of her vehicle while changing lanes on a wet street.

Police say Diaz’s car crossed a median and was hit by a semitrailer. Daniel Diaz, a seventh-grader at Columbus Middle School, died at the scene. His mother was taken to a local hospital, then to an Omaha hospital, where she died.

The 52-year-old driver of the semitrailer refused medical treatment.