SEATTLE - A rock ambush nearly killed people on Interstate 5, and an even larger vandalism spree has targeted homes in the same area.

Police don't know who is throwing rocks, but now it has escalated. Not just homes and parked cars are being targeted, now it is big rigs moving at freeway speeds.

Washington State Patrol is trying to track down the person who threw large rocks at drivers along Interstate 5 early Wednesday morning. One of those rocks came crashing through a truck driver's windshield.

The truck driver described the heart-stopping sound of the massive rock that crashed through the windshield of his semi-truck.

"It sounded like a bomb went off - ka-boom!" said the driver, who identified himself as David.

David was headed southbound on I-5 through Federal Way around 2 a.m. when someone launched the rock from the side of the freeway. The rock narrowly missed David's head, but broken glass sprayed across his face.

"I had to grab the wheel and couldn't see where I was going," said David. "I had to think to myself, 'Where are all the cars? How can you bring this semi down without hurting anybody?'"

David was able to do that, but he was hurt himself. Paramedics rushed him to Saint Joseph's Hospital with pieces of glass in his eye.

Two other vehicles were also hit with rocks. Fortunately, those drivers were not injured.

Police have stepped up patrols in the area, trying to hunt down the person responsible. Witnesses say they saw a man on the side of the freeway throwing rocks, but there were no good descriptions since it was dark.

"I'd almost have to call it a terrorist act, because you've got to think, or at least I would, of how much damage you can do with a loaded semi," said David. "I mean, they're worse than a gun."

David hopes whoever did this is caught before someone is seriously hurt. As for David, he's suffering from blurred vision but in the end he considers himself more than lucky.

"I think my guardian angel works overtime on me," said David.

David said he just got a cell phone at his wife's insistance. He's glad he had Wednesday morning to call 911.

Police don't know who is throwing rocks, but now it has escalated.

Larry Stefano's world was turned upside down when his Federal Way home was targeted by a large rock. His custom picture window was destroyed and glass littered his living room.

And he's not alone.

Just up the street, Laura Tuey's daughter’s brand-new car was hit last week and the back window was shattered.

Police don't know if the rock attacks are individual, isolated incidents or if there is a connection between the homes and the freeway occurrences.