Less than 36 hours after the Highway 401 accident that claimed two lives and resulted in a dramatically fiery scene unlike anything witnessed on local roads before, the east-west route was finally reopened Thursday morning, albeit with some lane closures as the substantail cleanup effort continues.

OPP Sergeant Kerry Schmidt has been on the ground updating the public since all lanes of the freeway were blocked off Tuesday night, posting videos of the astonishing aftermath of the crash that involved a passenger vehicle and two tanker trucks, one of which burst into a colossal fireball that burned for hours.

I know y'all seen plenty videos of the Pickering fire but this one making the rounds in the family chats is the wildest. pic.twitter.com/Dp9a8dXvPX

— Radheyan Simonpillai (@JustSayRad) June 22, 2023

Footage that emerged on social media from both the time of the collision and from shortly afterwards served as shocking fodder for speculation about what could have possibly happened to cause such spectacular, blazing chaos, but it's the clips from after the fact that help us better understand the incident.

It was just after 10:30 p.m. on June 20 when the driver of one of the trucks, which was carrying fuel, lost control of the vehicle while going eastbound near Brock Road in Pickering.

The tractor-trailor ran into the concrete wall of the street's overpass, rolled over, ruptured and caught fire, the inferno quickly igniting the cargo, which spilled out over the ground and into sewers below.

The driver died, while two closely following vehicles also caught fire, another big rig (the driver of whom also sadly passed), and a car containing two individuals who were able to survive without injuries.

Update: The OPP on scene investigation is complete. The MTO is assessing the condition of the overpass, road surface, and other infrastructure. Morning traffic may still be affected. Plan for alternate routes. #Hwy401/Brock Rd - Pickering. #TorontoOPP ^ks pic.twitter.com/JKFgtCz2FI

— OPP Highway Safety Division (@OPP_HSD) June 22, 2023

The Ministry of Transportation spent hours assessing whether the overpass bridge, nearby streetlights and the road infrastructure itself were safe to use and what repairs would be needed.

At least one towering lamppost has been taken down since, visibly burnt, while the concrete bridge also still appears completely blackened.

Update: Cleanup ongoing after fatal collision #Hwy401/Brock Rd Pickering. Plan alternate routes if you typically travel through this area. Updates to follow. #TorontoOPP pic.twitter.com/Tu1bNGcnts

— OPP Highway Safety Division (@OPP_HSD) June 21, 2023

Schmidt shared to Twitter yesterday afternoon how the lit fuel not only blanketed the roadway in fire, but also leaked into catch basins below the asphalt, causing explosions that blew multiple manhole covers fully off and destroyed portions of the freeway.

"Again, this is just showing some of the unbelievable power from those explosive fumes and fuels that blew out of these catch basins some distance from where the transport truck lost control and burst into flames," he said.

Wow

— susan baker (@susanbaker57) June 22, 2023

As of Thursday afternoon, the investigation has now moved off of the 401 and is still set to continue "for some time."

Travel has resumed in both directions with eastbound lane restrictions, while Brock Road south and the on-ramp to the highway remain shut down.