A man and two children were found dead and a woman critically wounded Tuesday evening in an apparent murder-suicide in a home southeast of Phoenix, authorities said.

Pinal County sheriff's deputies were called at about 5 p.m. to conduct a welfare check on the family in San Tan Valley east of Queen Creek. Relatives told authorities they became concerned after calling the home all day with no response.

Deputies entered the home and found the bodies of a 45-year-old man, a 10-year-old boy and an 8-year-old girl, said sheriff's spokesman Tim Gaffney.

The dead man's 37-year-old wife was flown to a hospital and was reported to be in critical condition.

All the victims were shot in the head, but investigators said they couldn't immediately determine whether the man or woman was the shooter. Gaffney said the victims' names were being withheld until relatives were notified.

Gaffney said the dead man and wounded woman were married and the woman was the mother of the two children. But he said it wasn't immediately clear if the man was the biological father of both children.

Gaffney said investigators were trying to piece together information on the family by interviewing relatives at the scene, but it was difficult because the relatives were "in a hysterical state."