(CNN) -- A county sheriff's deputy killed his ex-wife in a convenience store parking lot Monday, then shot a Virginia state trooper before being seriously wounded himself, police said.

Roanoke Police Chief Chris Perkins told reporters Monday that a murder warrant has been received for Jonathan Agee, who is now at Carilion Roanoke Memorial Hospital after suffering multiple gunshot wounds following a shootout with a pair of Virginia state police officers.

The bloodshed began at 11:30 a.m., when Jennifer Agee, 30, pulled into a Sheetz convenience store parking lot in Roanoke, Virginia, Perkins said. Trailing behind her in a marked Franklin County sheriff's office car was her ex-husband, Jonathan Agee. The 32-year-old sheriff's deputy from Boones Mill was off-duty at the time.

Perkins said that Agee and his ex-wife both got out of their cars. Jonathan Agee then shot Jennifer Agee, while another person believed to be a child sat in her vehicle, according to the police chief.

Jennifer Agee, who lived in Salem, was then taken to Carilion Roanoke Memorial Hospital where she died, Perkins said.

Almost immediately afterward, police issued an alert asking authorities to look out for Agee's sheriff's office vehicle.

Virginia State Police Superintendent Steven Flaherty said that Sgt. Matt Brannock spotted the marked car on Route 460 and followed it. At about 11:48 a.m., the two vehicles stopped at the Ironto exit ramp off I-81 ramp in Montgomery County.

There, Jonathan Agee opened fire and shot Brannock "at least once," Flaherty said.

Two other state police officers soon arrived at the scene, exchanging fire with Agee. They subdued the suspect after shooting him "several times," Flaherty said.

Both Brannock, a 35-year-old U.S. Air Force veteran who joined the state police force 13 years ago, and Agee were flown by helicopter to Carilion Roanoke Memorial Hospital. Police said the suspect's injuries are considered life-threatening, but those suffered by the state trooper are not.

This incident tied up Memorial Day traffic in parts of western Virginia, after authorities closed several lanes on I-81 northbound to give them more space to conduct their investigation.

Those lanes reopened shortly before 7 p.m., said Virginia State Police spokewoman Corinne Geller. But in the subsequent hours, traffic still moved slowly through Montgomery County due to the earlier back-up and influx of holiday travelers.

CNN's Greg Botelho contributed to this report.