ARNOLD, Mo. – We are learning more about the man who police say shot Officer Ryan O'Connor and then killed himself.

Chad Klahs was convicted of a slew of charges. The most recent conviction on his rap sheet involves Klaus making threats to kill.

In 2013, Klahs pleaded guilty to harassment or tampering with a witness. That same year, he also pleaded guilty to misdemeanor stealing and felony possession of chemicals with intent to manufacture a controlled substance.

The witness in the harassment charge said Klaus threatened to shoot the victim and made these threats several times a day.

He also told police he feared for his and his family's safety.

Erica Beaver is a friend of the family said he was not well liked.

"Everyone just hated him,” Beaver said. “I'm the type of person I don't judge nobody.”

She says she knew Klaus from the time he was in diapers

“I never thought he would go as far as shooting a police officer,” Beaver said. “Definitely it is a little hard to swallow."

Along with the 2013 convictions, Klahs was convicted of one count of assault and three counts of burglary, all in 2010.