4 people and family dog stabbed during scary home invasion

BUFFALO GROVE, Ill. -- It’s still unclear what motivated the stabbing of four people and the family dog during a horrific home invasion Wednesday.

Police say two men wearing masks burst into the house on the 400 block of St. Mary's Parkway near midnight. Four people were stabbed in the attack, as well as the family’s German Shepherd.

Despite serious injuries from multiple stab wounds, the homeowner managed to break away and retrieve his gun, according to investigators. He opened fire on the two masked invaders, who fled.

Up the road in Wheeling, an alert gas station attendant grew suspicious when he saw a group of men enter his store with bloodstains on their clothes. Police responded to the scene and say they detained one suspect with blood on his pants and a bloody hunting knife.

Sources familiar with the investigation tell us the homeowner is in serious condition after suffering stab wounds to the head, shoulder, and chest, puncturing his lung and narrowly missing his heart. Three other stabbing victims were treated and released, while Animal Control helped transport the dog to a veterinary hospital.

Three Persons of Interest were being questioned about the stabbing at the Buffalo Grove Police Department Wednesday. Police say they don't believe it was a random act.