The accident happened at 20.25 on Friday evening.
The stop affects SL's commuter train between Märsta and Södertälje as well as trains on the Stockholm C – Uppsala route via Märsta.
SL states on its website that it is possible to travel by bus 583 between Arlanda and Märsta. Commuter trains to and from Uppsala C go as usual.
There is no forecast for when traffic may be up and running again.