(CNN) -- A Houston police officer fatally shot in the head a schizophrenic, wheelchair-bound double amputee threatening people with a pen at a group home for the mentally ill after authorities said the man advanced on the officer's partner, police said.
The shooting occurred early Saturday morning after police responded to a call that resident Brian Claunch was acting aggressively after his caretaker refused to give him a cigarette and a soda, the owner of the home and police said.
"The officers made verbal commands for the suspect to drop whatever he had in his hand, to stay still and to speak with the officers, but the suspect continued to make threats," Jodi Silva, a police spokeswoman, told CNN affiliate KTRK in Houston.
Claunch, who lost an arm and a leg in a train accident, trapped one officer with his wheelchair in the corner of a room "where he couldn't get out," said a Houston police department spokesperson who declined to be identified. The double amputee was "advancing towards" the officers and "refusing to show his hands."
According to police accounts reported in the media, including by KTRK, Claunch attempted to stab the officer with an object that turned out to be a pen.
Officer Matt Marin, "in fear of the safety of his partner and the safety of himself, discharges his duty weapon, striking the suspect," Silva said.
The unnamed Houston police spokesperson said later Sunday that Marin himself was not cornered, unlike his partner, when he shot the wheelchair-bound man in the head.
According to investigators, Claunch was shot once and he died at the scene.
It was the second time Marin was involved in a shooting. In October 2009, he shot and killed a knife-wielding man who stabbed his girlfriend and a neighbor, according to published reports at the time. Marin joined the Houston Police Department in 2007.
In the wake of the weekend shooting, the officer was placed on administrative leave per department policy, according to police.
Claunch, who was in his 40s, had been at the Healing Hands home for 18 months, John Garcia, the owner of the group home, told KRTK.
Houston police have not released the identity of the man, though Garcia identified him as Claunch.
Garcia told the Houston Chronicle that Claunch liked to "doodle."
Two days earlier, Garcia gave Claunch a black felt pen to draw. Garcia told the newspaper he did not know if it was that pen or another one that Clauch had in his hand when he was shot.
Garcia said Claunch suffered from schizophrenia and a bipolar disorder.
"He had a temper. He could fly off once in awhile," he told CNN affiliate KHOU.
Claunch was capable of making people in the house feel threatened during an outrage, even though he was confined to a wheelchair, Garcia said.
"Emotionally disturbed individuals, when threatened, are going to react in most instances, excessively," Dr. Ed Reitman, a clinical psychologist, told KRTK.
"This was an incident that didn't have to take place if the individual -- a police officer -- had been trained in dealing with emotionally disturbed individuals."
The Houston Police Department has officers trained to deal with the mentally ill, though the department would not say whether Marin received training, according to KRTK.
NN's Nick Valencia contributed to this report.