THE HANDGUN used in a murder-suicide involving two doctors in South Jersey last week was the same weapon used to kill a North Carolina woman days before, according to reports.

On April 11, Dr. Giocondo "Joe" Navek, 39, ambushed and killed a former colleague, Dr. Payman Houshmandpour, outside Houshmandpour's Voorhees home before killing himself.

Five hours later, authorities found Navek's girlfriend, Shawna Givens, 35, dead in her Fayetteville, N.C., apartment. She hadn't reported to work at Womack Army Medical Center, in Fort Bragg, for two days, authorities said.

The Fayetteville Observer and other North Carolina media outlets have reported that ballistics tests had determined that the SIG Sauer handgun used in the murder-suicide also was the weapon that killed Givens.

Authorities found the handgun in Navek's vehicle after the shooting in South Jersey and suspected that he had killed Givens earlier.

Givens, a mother of three, had been dating Navek for about four to five months. The two met at the Womack Army Medical Center, where Navek, a captain in the Army Reserves, was stationed as a physician in the acute-minor-illness clinic.

Navek split his time between Fort Bragg and South Jersey, where he had lived in Williamstown with a woman, whom police identified as his fiancée, before she and their toddler son moved out recently.

The woman had recently broken up with Navek after she found out about his relationship with Givens, her mother said.

Contact Darran Simon at 856-779-3829 or dsimon@ phillynews.com, or follow on Twitter @darransimon.