A Bernardsville man who faces charges for a three-hour standoff with authorities last month could receive up to 10 years in prison after being convicted Tuesday of selling an Uzi and ammunition to an undercover detective in 2011, the Somerset County Prosecutor's Office said.

Samuel J. Medway, 44, was found guilty by a Somerset County jury of second-degree unlawful possession of an assault rifle, third-degree unlawful sale of an assault rifle, fourth-degree violation of the regulatory provisions related to firearms and fourth-degree forgery.

Jurors deliberated for three hours following the seven-day trial before Judge Julie M. Marino in Somerville.

Medway is due to be sentenced Sept. 21, the prosecutor's office said. He faces up to 10 years in prison with a mandatory-minimum of three years before being eligible for parole, the prosecutor's office said.

Medway's bail was revoked and he was lodged in the Somerset County Jail.

In June 2011, Medway sold an Uzi Mini Carbine semi-automatic assault rifle and 14 "large capacity ammunition magazines" with a total ammunition capacity of 409 rounds to an undercover detective for $1,500, the prosecutor's office said.

Medway was arrested shortly after the sale was made at his Anderson Hill Road home on June 28, 2011, the prosecutor's office said. Authorities searched Medway's vehicle, home and "studio-outbuilding" and found the fraudulent "bill of sale," a duplicate New Jersey Firearms Purchaser identification card that belonged to Medway and two Mossberg shotguns, the prosecutor's office said.

Medway's state firearms purchaser identification card and right to legally possess firearms had been revoked by court order in 2007, the prosecutor's office said.

Medway also is scheduled for an Aug. 6 appearance in Bernardsville Municipal Court on an obstruction of justice charge stemming from an alleged three-hour standoff with authorities, including SWAT team members, at his Anderson Hill Road home on June 7.

Authorities said there were no injuries resulting from the standoff, although there was uncertainty at the time of the incident whether Medway was armed.

Somerset County Prosecutor Geoffrey Soriano said the incident began when officers from the Somerset County Sheriff’s Office attempted to serve a failure to pay child support warrant in the amount of $93,432.01 for Medway on June 7 at about 6:45 p.m.

Residents in the immediate area were evacuated to the Bernardsville Library and nearby St. Elizabeth’s School by officers from the Bernardsville and Bernards Township police departments, the prosecutor's office said.

Medway eventually surrendered later that night at about 9:50 p.m., authorities on the scene said.