The sheer terror of motorists who encountered a Mitsubishi truck being driven erratically on the M1 motorway one Monday afternoon — with one passenger leaning out the window firing a nail gun at other vehicles — has been revealed in a harrowing set of police facts tendered to court.

Looking overweight and slovenly, Reid David Partlett, of Hamlyn Terrace, appeared via video link at Wyong Local Court on Tuesday, where he pleaded guilty to firing a nail gun at three other vehicles, striking two men — one in the head and the other in the arm — and then running from police after giving officers a false name.

The 20-year-old, who was 19 at the time, was a passenger in a Mitsubishi truck with number plates CK42UR that was travelling north on the motorway about 4pm on Monday, January 9 this year.

“The truck was holding up traffic and multiple cars were attempting to get around it,” an agreed set of facts state.

When one male driver “undertook” in the left lane to get around it, he noticed the middle passenger had something in his hands as the truck sped up to pull alongside his Toyota RAV4.

The driver and his male passenger heard a loud bang “as a nail was fired into the closed driver’s side window”.

His passenger wound down the window to take photographs of the truck in case there was any damage to the RAV4 and all three occupants of the truck “tried to hide their faces”.

“While the window was down the offender fired a nail into the RAV4, hitting (the driver’s) right bicep and causing swelling, bleeding and a red welt,” the facts state.

“(The victim) felt a sharp pain at the time it struck and looked down to see a nail sitting in his lap area.”

He sped away at 135km/h and called police.

Meanwhile a woman was driving a Hyundai Accent when she heard a noise and saw the truck pass her in the right lane.

About 10 minutes later she heard another noise only “10 times louder” and she “panicked” thinking someone was throwing objects at her before she saw the truck take the Wyong/Toukley exit.

“Terrified” she later saw two scratch/dent marks in her car.

Another man was driving a ute near the fixed speed camera at Ourimbah when he felt a sudden pain to the “left side of his scalp”.

“The significant pressure and pain that (he) felt caused his body to lean to the right which in turn caused his utility to steer to the right,” the facts state, before he was able to swerve back in control.

He looked around and saw the truck and a man’s head leaning out the window with a red shirt around his face like a bandana.

“He saw the offender put his hand over his mouth as if he was laughing and pulled up a red nail gun, aiming at (him). The offender fired two shots at (the victim’s) utility. The first hit the driver’s side door and the second hit the passenger side front window. The front window shattered. (The victim) took his cap off and noticed he was bleeding.

He saw the truck speed away “driving erratically” and he went to Toukley Police Station to report the incident with officers finding a “bloody nail sitting on the floor mat of the driver’s side”.

Police attended the Sparks Rd commuter car park and found three males standing around.

Two of them, Jarrod Swindley and Brea Monk, gave their names to police while Partlett gave a false name.

Mr Swindley and Mr Monk were not charged with anything and there is no suggestion either of them did anything wrong.

“Police recovered a red Milwaukee nail gun from the rear passenger section of the truck,” the facts state.

Partlett fled on foot and was seen trying to climb a fence but was far too obese because an officer followed and asked him twice to get on the ground.

Partlett squared up to the officer and “appeared to make a pair of fists with his hands” but was hit with pepper spray and arrested.

He pleaded guilty to hindering police and two counts each of recklessly damaging property and assault occasioning actual bodily harm with the nail gun.

On entering the pleas the Crown prosecutor withdrew six more serious charges including

two counts each of assault in company, being armed with intent and using an offensive weapon.

Those six charges were formally dismissed and Partlett was adjourned to face sentence on November 7.