The accident is causing serious delays on the trains in the region and no traffic will be able to pass through the scene of the smash until Friday.
Travellers along the southern Stambana line are having to take replacement buses between Linköping and Mjölby before continuing their onward journeys by train.
“[The delays] are about half an hour at a guess, three quarters of an hour,” said Magnus Andersson in the Swedish Railways (SJ) press office.
The accident happened at about 9.40pm when a northbound goods train loaded with timber came off the rails near Glyttinge campsite, between Linköping and Vikingstad.
A commuter train with 80 people onboard travelling southbound on a parallel track drove into the timber. On the first track, where the timber train derailed, many sleepers along a stretch of about a kilometre are damaged and need to be replaced before traffic can begin again. Around 100 metres of the other track is also damaged.
Neither of the trains could be removed overnight.
Seven people were taken by ambulance to the University hospital in Linköping, while around 70 passengers were offered bus transport to the hospital if they needed help.
According to a press statement from the hospital during the night, only one person, who was not badly injured, remained under observation.
The southern Stambana line carries traffic between Stockholm and Malmö and is one of Sweden’s most important stretches of railway.