A FEMA contractor is accused of killing a 67-year-old man in Florida months after he befriended the senior citizen while he was assessing the damage to his home caused by the deadly Hurricane Irma.

William Reiss, 68, was shot four times in the head in his Polk City home on January 3.

One of three young men arrested over his murder is Gerjuan Jackson - an 18-year-old official FEMA contractor.

Jackson was arrested in Mobile, Alabama last week with two other suspected accomplices.

William Reiss, 68, was shot four times in the head in his home in Polk City, Florida on January 3 allegedly by 18-year-old FEMA contractor Gerjuan Jackson

The teenager had met Reiss when he was inspecting his home following the deadly hurricanes last September.

During that time, police say Reiss showed the suspect his gun collection and later sold the teenager two handguns worth roughly $800.

Jackson was arrested soon after back in Alabama for improper possession of the guns, WFLA reports.

Police said Jackson then suggested to his two alleged accomplices that they should target Reiss.

Kenley Campbell, 22, and Darril Lamar Rankin Jr., 22, have also been arrested over the murder

Jackson allegedly went inside Reiss' home and gunned him down while Kenley Campbell, 22, and Darril Lamar Rankin Jr., 22, waited outside in the car.

Once the shots were fired, the other two men allegedly stole the victim's firearm collection and his flat screen television.

They are also accused of stealing his truck.

Police said Jackson set the truck on fire in a secluded area back in Alabama.

The three men have been charged with first-degree murder, attempted first-degree murder, armed burglary with assault/battery, 13 counts of grand theft of a firearm, robbery with a firearm/deadly weapon, conveyance burglary and grand theft of a motor vehicle.