A 45-year-old Army veteran has been identified as the disgruntled ex-employee who barged into his old office and shot five of his former co-workers dead before killing himself.

John Robert Neumann Jr went on a deadly rampage at the Orlando offices of RV awning company Fiamma at around 8am.

He shot and killed 69-year-old Robert Snyder, 44-year-old Brenda Montañez-Crespo, 53-year-old Kevin Clark, 57-year-old Jeffrey Roberts and 46-year-old Kevin Lawson.

Orange County Sheriff Jerry Demings said Neumann was fired back in April, and had a strained relationship with at least one of his former colleagues.

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John Robert Neumann Jr. (pictured left and right), 45, has been identified as the man who shot dead five of his former co-workers before killing himself Monday

Police officers are pictured outside the trailer park where Neumann most recently lived

Neumann had a slew of arrests for minor crimes including drug possession and DUI. He is seen in an array of mugshots from 1995 to his most recent in 2010. Police say he lived alone and did not have family in the area

Dennings quickly ruled out any link to terror in the wakes of recent attacks.

He said Neumann lived alone and didn't have any family in the area.

According to Army records, he was honorably discharged in 1999.

Investigators are 'trying to understand as much about [Neumann] as we can,' Demings said.

One of the co-workers was a sales managers while the others were former co-workers.

Friends of one of the victims, Kevin Clark, started a GoFundMe page for his family shortly after the attack.

The organizers revealed his 14-year-old cheerleader daughter Deleaney and 18-year -old football star son Gavin are now orphans.

Kevin Clark (left) was one of the employees Neumann shot and killed during his rampage along with Kevin Lawson (right), who was the father-of-four daughters

Robert Snyder, 69, was gunned down in the Monday morning attack. He was an avid billiards player at a bar in Orlando

Two other victims, 44-year-old Brenda Montañez-Crespo (left) and 57-year-old Jeffrey Roberts (right) were also killed

The pair's mother died nine years ago.

According to the Orlando Sentinel, he had only started working at Fiamma a short time before he died

His older brother, Chris Clark, said he started as a temporary employee before taking a full-time position.

Demings said his department received a 911 call at 8:03am about an active shooter situation at the company, which is located in an industrial park.

Officers were on the scene within two minutes, and found Neumann dead - in addition to three male victims and one female victim.

Another male victim was taken to Orlando Regional Medical Center where he was later pronounced dead.

Most of the victims were shot in the head and some were shot multiple times.

A disgruntled employee killed five of his former co-workers at an Orlando, Florida RV company Monday morning before committing suicide

The gunman - identified as 45-year-old Army veteran John Robert Neumann Jr. - was fired from Fiamma, an Italian-owned RV accessories company, in April

Four of the victims were male and one was female. Seven workers survived the incident. Above, a police investigator wipes away a tear at the scene

An investigator puts on paper booties as he inspects the crime scene on Monday

Witnesses said that the shooter arrived at the office armed with a handgun and a knife, but Demings said there's no evidence to indicate the shooter used the knife during the attack.

Demings said it appears that Neumann reloaded his semi-automatic pistol at least once during the shooting.

After shooting five of his co-workers, the shooter turned the gun on himself and committed suicide.

Seven other people were at Fiamma at the time and survived. There was also another witness who was a vendor.

They were taken to another location to be interviewed by police.

The shooting took place exactly one week before the one-year anniversary of the Pulse nightclub shooting, which also took place in Orlando. Above, officials on the scene of the shooting Monday

At a morning press conference, Orange County Sheriff Jerry Demings said that the shooter had been involved in another workplace violence incident at Fiamma three years ago

Officials say the shooting does not appear to be tied to terrorism in any way. The shooting comes on the heels of the Manchester and London attacks

One of the witnesses, a woman who worked as a temp, said that when Neumann arrived at the office, he pointed a gun at her and told her to get out - suggesting that he was only targeting people he had worked with during his time at Fiamma.

There wasn't any security cameras running inside the business, but there was one outside by the rear entrance where Neumann is believed to have shot the first victim, Demings said.

Demings had a minor criminal history including arrests for marijuana possession, DUI and misdemeanor battery.

He said that officers were called to Fiamma three years ago, when the shooter allegedly battered a co-worker.

Police are pictured at the home of shooter John Robert Neumann Jr who went on a deadly rampage

The shooter lived alone and didn't have any family in the area. His home is pictured above

A long box is seen being carried from the killer's trailer home in Florida

However, no charges were filed at the time.

Demings also said there was nothing to indicate that the shooting was related to terrorism, and that it's likely a 'workplace violence incident'.

The shooting comes on the heels of the Manchester and London terror attacks, and exactly one week before the one-year anniversary of the Pulse nightclub attack, which also happened in Orlando.

Forty-nine people were killed inside the nightclub by ISIS-inspired gunman Omar Mateen in what is now the deadliest mass shooting in U.S. history.

A police officer talks on the phone outside the scene of the shooting Monday morning

Police blocked off the street in front of the business Monday morning, rerouting traffic around the area

Above, a look at the crime scene vehicle that were brought to Fiamma on Monday

Shelley Adams said her sister, Sheila McIntyre, called her from Fiamma's bathroom during the shooting and was very upset.

She kept repeating 'My boss is dead. My boss is dead,' Adams said.

McIntyre was not injured. Adams described the company as a small business with only around 10 employees.

The FBI joint terrorism task force has an official on the scene, aiding in the investigation.

Authorities closed the road near the scene and have urged motorists to 'use caution'.

Fiamma is an Italian-owned company that makes accessories for RVs