An angry ex-husband charged in a shooting rampage at a California hair salon pleaded not guilty Tuesday to killing his former wife and seven others.

Dressed in an orange jail jumpsuit, his face partially covered by a thick moustache and beard, Scott Dekraai was arraigned on eight counts of murder and one count of attempted murder. The bloody onslaught at Salon Meritage rattled the seaside town of Seal Beach last month.

Authorities say the 42-year-old donned a bulletproof vest before shooting his ex-wife, Michelle Fournier, her fellow stylists and patrons at the salon, and a man in the parking lot on Oct. 12. Dekraai was arrested nearby with help from witnesses and, according to court documents, told police he committed the shootings.

Prosecutors were seeking the death penalty for Dekraai, who was engaged in a lengthy, acrimonious custody dispute with Fournier over their 8-year-old son.

Prosecutor Scott Simmons said he expects Dekraai will mount an insanity defense -- and has sought to obtain records from his psychiatrist in preparation.

"Our position is he was absolutely not insane at the time he committed the crime," Simmons told reporters after the hearing.

Defense attorney Scott Sanders declined to comment. Dekraai was being held without bail.

Two dozen relatives of victims crowded the Orange County courtroom for his arraignment, wearing T-shirts in support of the tight-knit beach community and buttons with their loved ones' photos.

After the hearing, Paul Wilson told reporters the focus should be on the victims, including his late wife, Christy, who worked at the salon, and not on Dekraai.

"My wife is the one who deserves all my energy -- not this coward who took her from me," he said.

Authorities say that on the day of the rampage, Dekraai took three handguns to a nearby beach where he pondered shooting Fournier. He then headed to Seal Beach, bursting into the salon and shooting eight people in the head and chest during a two-minute rampage. Only one of the victims survived.

After leaving the salon, prosecutors say, Dekraai shot to death a man sitting in his car in the parking lot, then drove away.

Authorities say Dekraai told police after his arrest that he shot Fournier, a friend of hers who had testified for her in the custody battle, and the salon's owner. Dekraai added that he saw the latter coming at him with a pair of scissors.

According to court papers, he said the other killings were "collateral damage."

A court-appointed psychologist had recently recommended the divorced couple's shared custody arrangement remain in place. Dekraai was pressing to change the boy's school and spend more time with him at his Huntington Beach home, according to Fournier's family law attorney, John Cate.

Family court papers show that Dekraai, a former tugboat operator, was diagnosed with post-traumatic stress disorder after a 2007 accident left him unable to work.

At a court hearing last month on the murder charges, Dekraai's prior attorney said his client wasn't receiving his needed antipsychotic medications in jail.

Dekraai's son is being cared for by his 24-year-old sister, Chelsea Huff.