SACRAMENTO, Calif. (AP) — A rookie Sacramento police officer was shot during a domestic violence call and lay wounded for about 45 minutes as the gunman kept officers at bay with bursts of fire, authorities said Thursday. She was finally rescued with an armored vehicle but died at a hospital.

"We are devastated," Deputy Chief Dave Peletta said. "There are no words to convey the depth of sadness we feel or how heartbroken we are for the family of our young, brave officer."  

Officer Tara O'Sullivan, 26, was shot Wednesday evening while helping a woman collect her belongings to leave her home. As officers swarmed the area, the gunman continued firing in a standoff that lasted about eight hours before he surrendered.

Stephen Nasta, a professor at the John Jay College of Criminal Justice and a former inspector with the New York Police Department, said taking 45 minutes to reach a wounded officer is "unacceptable."

If officers couldn't immediately get an armored police vehicle to the scene, he said, they should have commandeered an armored bank vehicle, bus or heavy construction equipment.