A gas leak has been found in an LPG tanker belonging to the same company involved in a fatal Sydney smash earlier this year.

The truck from Cootes Transport has been grounded, with NSW Roads Minister Duncan Gay threatening to take the company’s entire fleet off the road.

Two people were killed in the fiery smash on Sydney’s northern beaches in October, when a tanker overturned and exploded.

Roads Minister Duncan Gay on Thursday said the vehicle was prevented from operating until further notice.

Since the fatal crash, Mr Gay says NSW authorities had inspected 520 trucks, issuing 421 defect notices including 224 major defect notices and grounding 10 vehicles.

But he singled out Cootes for special mention.

“Despite assurances from the company’s board of directors and management they were on top of compliance issues within their tanker fleet, I’m quickly losing patience,” he said.

“The responsibility for vehicle maintenance sits firmly with the company.

“The short story is if they don’t shape up, we will have no choice but to ground the Cootes fuel tanker fleet in NSW.

“We have a clear duty of care to other road users.”

Roads and Maritime Services has directed Cootes’ parent company McAleese Group to provide a full account of the measures being taken to resolve safety issues within the company.

McAleese Group was contacted for comment.