Police said they were investigating the cause of the crash.
They were called to the scene about 8.30am.
The Serious Crash Unit has been notified and Fire and Emergency New Zealand confirmed it was there.
Hawke’s Bay Regional Council chair Sophie Siers said the “serious accident” involved Route 3 of the GoBay buses, which the council managed and planned.
“This is an extremely distressing situation, and our thoughts are with everyone affected.”
Go Bus chief operating officer Ben Barlow said the company’s thoughts were with the family and loved ones of the deceased, and with those involved.
“We are fully co-operating with police as they carry out their inquiries. We are supporting our driver while the investigation continues.”
The crash happened close to a rail crossing on Tennyson St.
While it did not involve any trains or the railway, the rail crossing was within the police cordon.
“This morning the line has been closed pending police clearance,” a KiwiRail spokesman said.
“Some freight services are affected as a result.”