UPDATED 11.00AM: Nelson fire crews have extinguished the truck fire which caused nearby businesses to be evacuated this morning.

The truck caught ablaze while carrying 60 cylinders of gas around 630-am on Quarantine Road.

Several of the cylinders popped.

Cordons are still in place and nearby businesses remain evacuated.

Assistant area commander Des Irving said they can now start to slowly remove the cylinders from the truck.

"We were working with the company that owns the cylinders to start that process, and once that's done, we'll hand the scene over to the police crash investigation unit," he said.

The driver wasn't hurt.