A psychiatric patient at a Western Maryland hospital charged with plunging a seven-inch metal spike into the head of a nurse who was trying to restrain him had threatened to kill staffers and others, according to police charging documents filed in court Tuesday.

Craig Harris Zello, 50, who according to his mother has been institutionalized in state mental hospitals for many years, was charged with attempted murder, assault and reckless endangerment in connection with Monday morning’s attack at Thomas B. Finan Hospital Center in Cumberland.

An Allegany County District Court judge on Tuesday ordered Zello held without bail. The victim, who police said was badly injured, told investigators that he found Zello standing in a room at the hospital holding the spike and screaming at staff members that he “was going to kill them,” according to the court papers. The nurse has been released from the hospital, state authorities said.

The attack occurred about 10 a.m. Monday. The injured nurse said he ran to call for help and tried to subdue Zello using a riot shield. Maryland State Police said in court papers that troopers had to shackle Zello’s feet and hands and that a nurse injected him with medication to calm him down. Still, police said he tried to stand up and “screamed ‘kill me’ and that he would ‘kill us all,’ ” the court documents say.

Zello was last ordered institutionalized after being found not criminally responsible in 2006 in an attempted armed carjacking and assault in Carroll County. He was sent to Clifton T. Perkins Hospital Center in Jessup in 2004 while he awaited trial and was transferred to the Finan Center in August 2012, according to court records.

Craig Harris Zello allegedly stabbed a nurse with a seven-inch metal spike after threatening to kill staff members at a hospital in Cumberland. (Allegany County Sheriff’s Office)

Zello’s mother, Shirley Jean Serig, said a nurse told her a few days ago that her son was refusing to take his medication, lithium, to treat his bipolar disorder.

“He’s not violent unless he’s off his medicine for a long time,” Serig said in a telephone interview. “As long as he was on his medicine, he would give you the shirt off his back and help you in any way. If he wasn’t on his medicine, something should’ve been done to get him on his medicine. That’s why he was there, to be treated.”

Serig said her son’s life has been marked since childhood by repeated stays in hospitals and frequent medication changes. “All he wants to do is go fishing,” she said.

The hospital’s chief executive officer, Judith Hott, said that the campus is secure but not gated, and that some patients are allowed to leave, either on their own or with a staff member.

Authorities do not know how the spike was obtained, Hott said.

Zello’s mother said her son could leave the grounds; Hott declined to comment on a specific patient. She also would not say whether Zello had stopped taking his medication.

Hott said a task force has been formed “to understand how this happened and how to move forward in way that greatly minimizes anything like this from happening in the future.”

Jennifer Jenkins contributed to this report.