Honolulu — A dangerous Hawaii psychiatric patient who escaped a state hospital and flew to California before being captured on Wednesday has prompted an investigation into why employees appeared to fail to do their jobs.Dr Virginia Pressler, director of the Hawaii Department of Health, said an internal inquiry indicated that workers inadvertently or intentionally neglected to supervise Randall Saito and notify their supervisors.The apparent failures were spread through several shifts of workers, and employees will be placed on unpaid leave for 30 days during the investigation, she said. Saito was gone at least eight hours before hospital staff alerted authorities.Saito on Sunday left the 202-bed Hawaii State Hospital outside Honolulu, where he has been committed for 36 years since being acquitted of murder by reason of insanity.He took a taxi to a chartered plane bound for the island of Maui and then boarded another plane to San Jose, California, authorities said.It wasn't immediately known how he was able to charter a plane, and police wouldn't provide details about his flight to California. Attorney General Doug Chin said the escape was planned and an investigation would include an examination of whether Saito had any accomplices.Honolulu police received a tip that Saito was on his way to a brother's home in the city of Stockton and forwarded that information to California authorities, Honolulu CrimeStoppers Sgt Chris Kim said.Saito was captured in Stockton on Wednesday morning as the result of a tip from an alert taxi driver, the San Joaquin County Sheriff's Department said. The agency posted a photo on social media showing Saito surrounded by three deputies at a gas station.'Criteria of a classic serial killer'Saito has been charged with felony escape, and the attorney general said the breakout was not planned by someone suffering from a "mental defect".Hospital workers had called 911 to report Saito's disappearance shortly after 19:30 on Sunday — two hours after he landed in California, Honolulu police said. An all-points bulletin went out an hour later.Gov David Ige said authorities and the public should have been notified much sooner and directed Chin to investigate.He said the state has started reviewing patient privileges and public visitation policies at the hospital to determine if they are appropriate. It's also boosting the frequency of unannounced patient searches and ordering more fencing.Saito was sent to the hospital in 1981 after acknowledging he shot Sandra Yamashiro with a pellet gun and then repeatedly stabbed her in her car, which was parked at a shopping mall, according to court records."He is a very dangerous individual," said Wayne Tashima, a Honolulu prosecutor who argued in 2015 against Saito receiving passes to leave the hospital grounds without an escort.Defence attorneys sought to have Saito released in 2000. But Jeff Albert, a deputy city prosecutor, objected, saying Saito "fills all the criteria of a classic serial killer".In 1993, a court denied Saito's request for conditional release, saying he still suffered from sexual sadism and necrophilia.Psychiatrists who evaluated him over the years also said he could be personable, charming and had good social skills.Dr Gene Altman, who evaluated Saito in 2010, said he had six significant relationships since being committed in 1981.EscapeThree of those were reportedly with hospital staff members and the others were with women in the community, including Saito's first and second wives, according to Altman's assessment, filed in court records.It's unclear if those employees faced repercussions for the relationships. Officials said the relationships are part of the investigation.Irving Tam, who has lived near the hospital for about 30 years, said he heard about the escape from a neighbour, not the police, hospital or media, and that patients have gotten out several times in the past."When they do escape, especially someone with this kind of a record, there is a high degree of concern, he could be violent and who knows," Tam said on Tuesday.Dangerous psychiatric patients have escaped recently from other facilities in the United States, including a man in Washington state accused of torturing a woman to death.Anthony Garver crawled out of a window of his ground-floor room at Western State Hospital last year, rode a bus 483km to Spokane and was captured days later without incident.