Last night around 6:30 PM, Mesa County Sheriff's Office responded to a call where two young children needed immediate attention, reports KKCO. The incident left one 2 year old dead and a four year old on life support.

Two-year-old William Jensen died last night and his four-year-old brother Tyler was helicopter lifted to an area hospital -- he has been transferred to the Children's Hospital in Denver.

The two boys were said to be left in a red Toyota 4Runner that had been left running.

No information has been provided by the coroners office, we'll keep you updated as updates come in.