A 37-year-old New Hampshire man has been arrested on a charge of second degree murder for allegedly causing the death of his wife.

Authorities announced the arrest of Christopher Smeltzer of Auburn late Tuesday, a day after 39-year-old Mara Pappalardo was found in their home, together with the body of their son.

Attorney General Michael Delaney says the husband caused the death of his wife sometime between Sunday and Monday. A medical examiner determined that the cause of death was blunt impact injuries to the woman's head, along with ligature strangulation.

Authorities are still investigating circumstances surrounding the death of the couple's 4-year-old son who was also strangled to death. Their 7-year-old daughter sustained non-life-threatening injuries.

Smeltzer will be arraigned Wednesday. It was not immediately clear if he has an attorney.

(This version CORRECTS APNewsNow. Corrects age of man arrested to 37 instead of 39.)