SEATTLE, WA – The man who is wanted for the murder of a Seattle Metro bus driver was arrested a year ago for the murder of his roommate, but released due to a lack of evidence, according to the prosecutor’s office.

Seattle Police say 53-year-old Richard Sitzlack murdered 59-year-old Shawn Yim early Wednesday morning.

Yim, a King County Metro driver, only had two passengers on the bus when he was killed: the accused murderer and a witness, who FOX 13 Seattle spoke to on Thursday morning. 

Seattle Police released a photo of the accused killer more than 30 hours after the murder.

However, police tell FOX 13 Seattle someone reportedly saw Sitzlack downtown around 8 p.m. Wednesday. That is about five miles from where the attack happened in the University District, and 15 hours after the attack.

Seattle police would not provide any more details on the sighting of Sitzlack.

“We are seeking the public’s help in finding this person,” said Detective Eric Muñoz with SPD. “The Metro coach drivers all have his photograph, every police officer in the city has his photograph and information.”

A year ago, Sitizlack was behind bars for a similar incident.

Officials from the King County Prosecuting Attorney’s office said Sitzlack was arrested for murder in connection with the death of his roommate. 

However, no charges were filed, and Sitzlack was released.

“Both police and prosecutors looked at the admissible evidence and thought we can’t disprove the claim of self-defense,” said Casey McNerthney with the King County Prosecuting Attorney’s Office.

According to the prosecutor’s office, Sitzlack claimed his roommate tried to kill him with a machete. He fought back and stabbed his roommate to death, then called the police, according to the report. 

“If King County prosecutors had the evidence to charge him with murder, we would have charged him with murder,” said McNerthney.

The transit union is offering a $10k reward to the person who helps find the murderer. 

Anyone with information is asked to call the Seattle Police Department’s Violent Crimes Tip Line at 206-233-5000. 

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