***8:00pm: Roadway is open.
***UPDATE***
Roadway is open in both directions now. There is still a police presence in the area, with one lane for west bound traffic still closed.
Palmer Police are on scene of an injury accident on Palmer Wasilla Highway near Peak Inn Motel. There will be a presence there for an estimated two hours. Traffic coming from Palmer is being diverted into the CARRS parking lot and around the scene. If possible, please avoid the area while the investigation continues.
Original source can be found here.