A bus operated by the regional public transport company UL was also involved in the accident, which happened at around 4pm on Monday on an icy road 72 at Heby, about 40 minutes west of Uppsala.
"The passenger car tries to overtake the bus but does not see the tank truck in the oncoming lane so there's a head-on collision. It's to the extent that the truck then pushes the car in front of the bus," police spokesperson Linda Wideberg told the TT newswire.
Two men in their mid-20s died in the crash and the third person had not yet been identified by Tuesday morning. A fourth man in his 30s was taken to hospital in Västerås. The full extent of his injuries was not immediately known. They were all travelling in the car.
The accident happened on road 72 between Uppsala and Sala. Photo: Niklas Hagman/TT
Several people were on board the bus at the time, but none of them were injured.
The road was closed in both directions on Monday evening while the vehicles were being salvaged. It reopened shortly after 8pm, according to Swedish road authorities.