By Jermont Terry

MARKHAM, Ill. (CBS) — A longtime Chicago Transit Authority bus driver and his ex-wife were each found fatally stabbed in Markham, and police said Tuesday night that their own grandson was the killer.

Police described the scene as “horrific” and “bloody.”

The police chief in Markham said there were signs the grandfather tried defending himself, given the blood spatter all through the house. The grandson had recently moved into the house because he had nowhere else to go after getting out of prison.

As CBS 2’s Jermont Terry reported, a sport-utility vehicle still sat in the driveway at the home where the murders happened. But just looking at the home would not reveal the horror police said happened inside.

“Police said it’s the worst thing they’ve ever seen,” said Fran Jurek. “How in the world could you ever think of that?”

Gabriel Tyson, 68, affectionately known as Gabe, spent 20 years working as a CTA bus driver and lived on Sawyer Avenue in Markham for decades.

Gabriel Tyson

Gabriel Tyson

“We’ve been neighbors for over 27 years,” Jurek said.

And the Jureks new something wasn’t right when one of Tyson’s grandsons frantically knocked on the door.

“The grandson came over here and asked if we had a key,” Fran Jurek said.

“No one in the house was answering their phones,” added Kristyn Jurek.

So that grandson called 911. When Markham police arrived on the scene, they found Gabe Tyson lying in a pool of blood near the back door. Once inside, they found Tyson’s ex-wife – Carmella Tyson, 65 – dead in the room, also stabbed to death.

Police found the grandson who had been living with them in a bedroom, sitting calmly around kitchen knives.

Police said that grandson had recently moved in after getting paroled from prison in June. The grandfather had allowed the 21-year-old to stay with him.

“He had a good heart to let someone stay with you,” Fran Jurek said. “I sure, I wouldn’t if someone just came out of prison. I’m sorry. And I’m a Christian woman.”

Neighbors are grateful they didn’t give spare keys to the worried grandson.

“Thank God I didn’t find it, because he would have came in there and saw the scene,” Kristyn Jurek said.

What sparked the double murder remained unknown Tuesday night. The grandson will appear before a judge on murder charges later this week.