A stolen fertiliser truck has crashed into a building at Singleton in the Hunter Valley, sparking explosions and a major rescue operation, police have said.
The semi-trailer hit several cars and a building on the New England Highway at George Street, sparking a blaze.
"I can sympathise with the people that are actually involved with the situation," she said.
A spokesman from the Hunter rescue helicopter said a 67-year-old man had multiple injuries and was flown to John Hunter Hospital in Newcastle.
Police said that man was in one of the vehicles. He is in a serious condition with non-life-threatening injuries.
A second person was flown to John Hunter Hospital in a serious condition, while a third person was taken by road ambulance with shoulder and leg injuries.
A further two people were taken to Singleton District Hospital with minor injuries.
Police said the truck was stolen from a service station at Murrurundi.
Officers said the truck was sighted driving erratically south along the highway, through Muswellbrook and towards Singleton.
As the truck approached Singleton, officers deployed road spikes in order to stop the vehicle.
The truck continued into George Street, where it caught fire after crashing into several vehicles and buildings, including one next to the Royal Hotel.
A Fire and Rescue structural engineering team has been sent from Newcastle to assess the Royal Hotel building.
Gabrielle Brown, who saw the crash and subsequent explosions, said it was "pretty scary".
Ms Brown said she saw the driver try to flee, prompting several officers to draw their guns.
Police said the driver was arrested at the scene and is currently assisting with inquiries.
The critical incident team from Port Stephens Local Area Command is investigating the circumstances surrounding the incident including the deployment of road spikes.
In a separate incident, the Hume Highway was in lockdown this morning after a frozen-food truck crashed, bursting into flames on the Wingecarribee Bridge at Berrima in the NSW Southern Highlands.
The B-double truck crashed into a safety barrier and was hanging over the side of the bridge when it ignited shortly before 8:30am.
Footage of the crash shows black smoke and flames billowing out of the wreckage as it dangled from the roadway.
The truck driver, a man aged in his 60s, was treated at the scene before being taken to Bowral District Hospital with minor injuries.
Crews from the Rural Fire Service spent the morning trying to extinguish the flames and a small area of scrub that caught alight below the bridge.
The crash closed the Hume Highway in both directions for several hours but southbound lanes recently reopened.