Emergency services were called to the scene about 8.10am after reports of a collision between a truck and a bicycle.

A 36-year-old man was trapped under the truck and died at the scene.

A crime scene was established and Minmi Road was closed while the Newcastle Crash Investigation Unit carried out an examination.

The truck driver was uninjured and was taken to John Hunter Hospital for mandatory blood and urine tests.

Investigations are continuing and a report is being prepared for the coroner.

Meanwhile, a motorcyclist, 42, suffered a partially severed finger as well as neck and leg injuries when he came off his bike on Putty Road yesterday afternoon.

A Westpac rescue helicopter service spokesman said the man was about two kilometres south of Putty when the crash occurred.

He was transported to Westmead Hospital in a serious condition.

Another motorcyclist came off his bike in the Upper Hunter on Saturday morning, causing the closure of the New England Highway.

Police said a group of riders was heading north on the highway at Whittingham, five kilometres south of Singleton, about 10.50am.

Two riders reportedly came off their motorbikes with the second rider crashing down an embankment.

The 28-year-old victim from Thornton suffered a shoulder injury and he was airlifted to John Hunter Hospital.

The Westpac helicopter was unable to attend, forcing a Sydney chopper to travel north to the accident.

As a result the New England Highway was closed for almost two hours.

The northbound lane was closed from about 11.30am while the southbound lane was closed from about 12.10pm.

Both lanes reopened to traffic about 1.25pm.