A groom is one of two people fighting for life after a minibus rolled several times down an embankment on the way to a wedding venue in NSW’s Hunter Valley.

Six people — the driver and five passengers — were onboard the bus when it veered from Mount View Rd at Mount View, about 10.45am on Wednesday.

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The crash occurred at the turn-off to Carillion Wines and Bistro Molines, on Tallavera Gr, according to Live Traffic NSW.

The vehicle went down an embankment, rolled up to seven times, and finished about 150m from the road, according to authorities.

“I can confirm the persons on the bus were in fact a groom’s party,” NSW Police district commander Superintendent Steve Laksa said.

“The groom of the wedding was actually on the bus, a 56-year-old male person who suffered serious injuries.”

The groom is understood to have suffered limb injuries and another passenger aged in his 60s has head wounds.

Both were in a critical condition and rushed by helicopter to John Hunter Hospital, while the other four injured people were taken to the same facility by ambulance.

The driver will undergo mandatory blood and alcohol testing, Laksa said.

NSW Ambulance Superintendent Jake Broughton-Rouse said it was “a really difficult scene”, with the vehicle rolling about seven times and finishing “about 150m down an embankment”.

“It took a multi-agency and really co-ordinated response to gain access to the vehicle,” he said.

“It took approximately 45 minutes to cut one of the patients out of the minibus.”

Laksa described it as a “tragic situation”.

“They hadn’t actually got to the wedding yet so they still have a wedding in front of them,” he said.

“We’re very fortunate that the injuries were not fatal.

“It definitely could have been worse.”

The crash is now under investigation from NSW Police to “try to identify the cause of the accident”.

Police are looking into whether passengers on the minibus were wearing seatbelts, and if wet weather conditions played a part in the crash.

“The only information we have at the moment is that (the bus) has veered from the road,” Laksa said.

“There has been some details provided in how that may have occurred but that will be a matter for crash investigation.”

Police Minister Yasmin Catley said: “This is horrific news and my thoughts are with everyone involved.

“I want to thank the first responders who are working in challenging conditions to assess and care for the injured.”

Police say while the particular stretch of road is not known for accidents, there have been 15 fatal vehicle crashes in the Hunter Valley police district this year alone.

“So 15 souls have lost their lives on local roads so we appeal to the community, to parents, to mums and dads to speak to their kids and their loved ones to say just slow down on the roads, and be very wary of the use of alcohol and drugs and fatigue,” Laksa said as a general warning.