 -- An Illinois police officer's death has been ruled a suicide, officials said today, two months into the investigation of his shooting death.

Fox Lake Police Lt. Charles Joseph Gliniewicz died by a "carefully staged suicide," Lake County officials said at a news conference today.

Gliniewicz "committed the ultimate betrayal," officials said.

The investigation found the lieutenant had been committing "extensive criminal acts," including stealing and laundering money from the Fox Lake Police Explorer Post over the past seven years, officials said. Thousands of dollars were used for personal purchases, including adult websites, officials said.

The Police Explorer Post helps youth who are interested in careers in law enforcement. The Fox Lake Law Enforcement Explorer Post 300 website lists Gliniewicz as an advisor.

He was also found to have forged signatures and official documents, officials said.

Authorities determined Gliniewicz intentionally left a staged trail at the crime scene to try to mislead first responders that this was a homicide scene. Gliniewicz had significant experience staging mock crime scenes as a part of his job, officials said.

Gliniewicz was found shot dead in the Chicago suburb of Fox Lake, Illinois, Sept. 1, shortly after he radioed that he was chasing three suspects.

The shooting led to an extensive manhunt for the three alleged suspects. The subjects described by the officer were since found and interviewed by authorities who determined they had "rock solid alibies," officials said today.

Gliniewicz's "ongoing criminal activity" was revealed by analysis of his text messages and financial records, officials said.

"The stress in his life began six months ago," officials said today, when, according to Gliniewicz's text messages, he was feeling pressure with new management in the Village of Fox Lake. According to officials, the Village of Fox Lake had begun conducting an internal audit of its assets, which would have eventually led to the discovery of the officer's criminal actions.

Gliniewicz was 52 and nearing retirement after more than 30 years with the police department.

A statement today from the attorneys for the Gliniewicz family said: "Today has been another day of deep sorrow for the Gliniewicz family. The family has cooperated with the Task Force's investigation and will not comment at this time. The Gliniewicz family requests that their privacy be respected as they continue to cope with the loss of the beloved husband and father."

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