JACKSONVILLE, Fla. -- A mental-health patient who refused to drop two steak knives after being shocked with a Taser gun was shot and killed by an officer after getting up and moving threateningly toward the officer, according to the Jacksonville Sheriff's Office.

The incident began just before 11 a.m. when a caseworker was making a daily check on 30-year-old Sierra White at his apartment in the 3400 block of Townsend Boulevard. Police said that after the caseworker was met with some resistance from White, she called for officer assistance.

With White's behavior becoming increasingly erratic and threatening, he went back inside his apartment and officers thought he heard the sound of a gun being loaded. The officers took cover, but continued to try to talk to White.

"At some point in time, the client withdrew two knives -- one from each pocket -- in each hand," said Jacksonville Sheriff's Office Chief Rick Graham.

When White began to move toward police, two officers deployed their Taser guns.

"The subject went down, continued to hold onto the knives. At one point in time, got up as if he was going to come back at the officers. They again tased him," Graham said. "It was having no effect."

Graham said that despite four shocks with Taser guns, White got back up on his feet and began to move toward Sgt. Rob Beers, and the officer fired his service revolver, hitting the man several times.

"I heard the five shots when I was in the bed. That's what made me come out and see what was going on," said neighbor Calvin Lewis. "He was laid out on the floor, and the police had shot him."

Just before noon, Jacksonville Fire-Rescue confirmed that White was dead.

Graham said the dialog with White had gone on for several minutes before the violent altercation began.

"The officers tried to do everything in their power to try and keep from using lethal force on this subject," Graham said.

Nelson Cuba, with the Fraternal Order of Police, said most officers are trained to handle crisis situations with mental patients, but he said those types of situations can become just as dangerous for officers.

"Whether it's a person with normal capacity who has a knife or one who has a mental disability with a knife, the danger is the same if not even more heightened," Cuba said.

He said Taser guns do not work on everyone; specifically, the tools will sometimes not work on mental illness patients as well as people who have been taking drugs.

According to investigators, the officers involved did everything they could to avoid shooting White.

Nonetheless, Lewis said he wishes more could have been done for his neighbor.

"We don't know what was going through his mind, and we do have different kind of tactics and things we can do to calm a person down, so I personally don't think that he still should of got shot," Lewis said. "Anytime you've got a human being that has to lose their life in that kind of situation, it's always sad."

Beers was placed on administrative leave, which is standard practice while police-involved shootings are investigated.

Police said they had not yet entered the man's apartment, so they could not say whether White had a gun.

Townsend Boulevard was closed for much of the afternoon while crime-scene technicians processed the scene.

This is the eighth police-involved shooting of 2008 and the fifth person to have died in the incidents. One police officer was shot in the altercations. That officer is recovering from his injuries.