Police said alcohol and speed may have been factors in a car crash that killed a man and injured his two children in Sultan.

Police said the man, his 11-year-old daughter and his 5-year-old son were on their way back from a day at Lake Spada near Sultan on Sunday when their car crashed off Sultan Basin Road.

Investigators said the skid marks on the roadway show the driver, a 35-year-old Sultan-area man, drove off the roadway, over-corrected and lost control of the car, which slammed into a tree and flipped.

The driver was killed and his children were seriously injured.

At the crash site, investigators cut away at the trees as they worked to figure out what caused the accident.

“Speed and alcohol are possibly involved in the crash. It looks like the vehicle was going too fast, left the roadway and crashed,” said Snohomish County Sheriff’s Office Det. George Metcalf.

Officers said the children usually live with their mother in Tacoma and were visiting their father.

They were transported to Harborview in serious condition.