The 71-vehicle pile-up occurred in mid-January on the E4 motorway near Helsingborg, southwestern Sweden. One person was killed and dozens were injured as traffic on the both lanes of the Tranarpsbron bridge skidded to a halt.
"It's been a mammoth piece of puzzle solving but we're approaching the end now," investigator Arne Davidsson of the local police told the Helsingborg Dagbladet newspaper (HD) on Monday.
IN PICTURES:The scene January's crash
After the two-month probe, police now suspect eight drivers of reckless driving, including not leaving sufficient distance between themselves and other motorists considering the icy conditions.
"Tranarpsbron bridge could almost be compared with two tunnels. The emergency services couldn't come in from the side or from above. All the work had to be done from either end - just like if it had have happened in a tunnel," Davidsson said.
Another driver is suspected of manslaughter after the trailer of his truck killed a driver from Lithuania who had exited his vehicle and was helping warn other motorists to slow down.
Of the eight suspected drivers, seven are truck drivers and one was driving a car. Five of the drivers are Swedish.
The crash involved 38 trucks and 33 cars.