A deadly multi-vehicle crash that closed down a stretch of Interstate 75, also known as Alligator Alley, in Collier County early Friday morning remains under investigation.

Florida Highway Patrol (FHP) said three commercial truck and four passenger vehicles were involved in the crash, which occurred on I-75 near mile marker 96.

One of the trucks involved was stopped within a travel lane due to low visibility from smoke in the area when another truck crashed into the back of it, FPS said.

That crash, FHP added, led to a chain reaction crash that involved five other vehicles.

At least one person was killed, two other people received serious injuries and one person received minor injuries.

FHP said in addition, three more crashes occurred in the northbound lanes on I075 at mile marker 95. No injuries were reported in those crashes, FHP said.

Both sides of the highway have since been reopened.