Kansas City man arrested after amassing arsenal of weapons, security items

Robert J. Gross appears in a Kansas City Police Department booking photo. He went to trial Monday on interstate stalking and firearms charges.
Robert J. Gross appears in a Kansas City Police Department booking photo. He went to trial Monday on interstate stalking and firearms charges. Kansas City Police Department

FBI agents may have averted gun violence when they arrested a 66-year-old Kansas City man allegedly buying shotguns in the parking lot of a home improvement store in Liberty.

They took Robert J. Gross into custody Friday evening and he was charged Tuesday in federal court with illegally possessing firearms.

According to court records, Gross spent the past several weeks amassing a collection of guns, handcuffs and other security paraphernalia. He is currently on bond for a charge of aggravated sexual battery in Douglas County, Kan. He served time in a federal prison in the 1990s for threatening a former girfriend, possession of cocaine and interstate transportation of a stolen firearm.

“Gross has a history of interest in prostitutes, including deviant sexual and violent behavior, particularly against women, dating back to at least 1975,” according to the complaint filed Tuesday in U.S. District Court in Kansas City.

Gross had been under FBI surveillance for three weeks after he became suspected of property damage and stalking employees at massage parlors in Johnson County and in Lawrence.

Employees contacted local police after their cars were keyed, their tires punctured and their windows knocked out.

According to the complaint, surveillance video from the Lawrence massage parlor on Oct. 1 shows a man, determined by federal authorities to be Gross, moving around the business naked, fondling himself, wrapping his arms around an employee and attempting to caress her face.

On Dec. 2 the FBI observed Gross go to a surplus store in Kansas City, Kan., and purchase two black shirts with the word “SECURITY” on them, four pairs of handcuffs and two balaclavas, or head coverings used to conceal identity. A manager later told officials Gross had been in the store two weeks earlier and bought two pairs of cuffs at that time.

On Dec.16 the FBI observed Gross inquiring about guns, including an “Uzi-type” firearm, at a gun show at the KCI Expo Center. A federally licensed dealer told investigators Gross had asked him about powerful guns, said he was a cash buyer and “seemed very nervous.” Gross went back to the gun show the next day and examined a Luger handgun.

On Friday the FBI observed Gross return to the surplus store in Kansas City, Kan., and buy four more sets of handcuffs and another balaclava. He also inquired about buying a bulletproof vest.

Gross was arrested Friday evening after allegedly paying $350 for two 12-gauge shotguns from a seller he had contacted after finding him online. As a convicted felon, Gross is not allowed to possess guns.

“As the surveillance team approached, Gross was observed being in possession of two shotguns, holding one in each hand as he was putting them into the trunk of his vehicle,” the federal complaint said. “Gross was ordered to drop the guns which he complied [ sic ] and he was taken in to custody.”

A detention hearing is scheduled for Friday.

Matt Campbell: 816-234-4902, @MattCampbellKC