A SPECTACULAR truck collision on SH1 near Marton last night is likely to keep the North Island Main Trunk railway line closed for a lengthy period. The rail overbridge on SH1 near the intersection with Calico Line was left a mangled wreck after a B-train truck and trailer unit involved inthe accident smashed into a main supporting pylon and caught fire. The fire spread to the overbridge, making life difficult for firefighters who were forced to battle the spectacular blaze with the threat of 50,000-volt overhead electrical lines used to power rail cars. Marton chief fire officer Paul Hudson said the accident appeared to have happened after the two trucks travelling in opposite directions on SH1 clipped, propelling the B-train into the overbridge just after 9pm last night. "It appears the two trucks clipped each other and one has crashed into the overbridge pylon before bursting into flames. I don't know how, but both drivers made it out unscathed and the second truck wasn't involved in the fire," Mr Hudson said. "The truck on fire was carrying general freight, which included plastic pipes. "Once plastic catches fire it's difficult to extinguish. "The rail overbridge was severely damaged, and I'd say the Main Trunk line will be closed for some time while it's repaired," Mr Hudson said. Inspector James Taare, of the police communications centre said late last night that once the truck had been removed the bridge would need to be examined by a structural engineer before trains could continue to use it. Fire crews from Marton and Hunterville arrived from the north of the rail bridge, while crews from Bulls attacked the blaze from the south. PICTURED: Emergency crews battle the blaze that left the main road and rail corridors closed through the night after a spectacular fiery truck crash near Marton.