What to do in case of an accident with a person from another country?

The person driving, was traveling to work, when a tractor truck hit the car from behind. He ( the driver of the tractor truck), took pushed the car for a whiled before the car finally began to spin out, hitting the middle divider on the highway. The car that got hit is a 2002 Honda civic, both doors; the drivers and the back passengers were damaged to the point where you can't open the door, also broke one of the wheels on the right side of the driver. The car is a complete loss, while the tractor truck continued on his way. Police were called to the scene. An mentioned the driver driving the tractor truck was from Canada, with a Canadian insurance. While the accident occurred in Richmond, Virginia. (United States). Could anyone who has probable experience something familiar please give me some options of how I can proceed with this. Thank you.

Added (1). Excuse all the errors in my typing.

You contact your insurance company and let them handle it. It's that simple.

Does not matter where the other driver is from. Just let the insurance company do its job.

I see nothing in your "description" that says YOU were involved in this accident. If YOU were not the driver OR the owner of the car, then it's none of your business.

I'm a retired truck driver. I drove US and Canada. To drive both countries you have to have insurance in both countries unless the truck was a company truck that was self-insured. Then all you have to do is call the company (BIG LOGO ON SIDE OF TRUCK, not the trailer unless the same company) Trailer ID number would tell exactly what truck was pulling the trailer at the time. Then the company will pay for damages. With company trucks you ALWAYS go through the company first to find out if they are self-insured. Most are as it is cheaper for them to pay for the damages than it is for the insurance.