A truck and trailer collided with a southbound freight train at a level crossing on Tararua Rd, Levin on Monday night at 9.10pm.
A witness said petrol was "pouring" onto the road.
No one was injured in the incident, police said at the time.
A Fire and Emergency spokesman said they attended the scene but soon left as there were no injuries or people trapped.
Police initially said the truck was carrying live pigs, many of whom died as a result of the impact, however people the
Horowhenua Chronicle
has spoken to said the truck carried only pig carcasses.
A KiwiRail spokesperson said the crossings barrier arms, bells and lights were all working at the level crossing. The incident happened at 9.10pm on Tuesday and there were no injuries. The line re-opened just before 2am.
"We understand the truck was carrying pig carcasses. KiwiRail trains do not carry livestock."