An 82-year-old Portland, Oregon, man died Thursday of injuries he suffered last month when he was brutally beaten during an unprovoked attack at a bus stop, authorities said.

Donald A. Pierce’s manner of death was determined to be a homicide by blunt trauma, the Portland Police Bureau said.

Pierce and a second elderly victim, described as an 88-year-old man, were at a bus stop in downtown Portland just before 8:30 p.m. on June 25 when a man attacked them without provocation, police said. 

Officers spotted the assault in progress while on another call in the area of Southwest 5th Avenue and Southwest Hall Street.

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The suspect repeatedly punched and kicked both elderly victims and continued to assault them after they fell to the ground, according to witnesses and video evidence obtained by police.

Portland assault homicide victim Donald Pierce

Donald A. Pierce, 82, died Thursday after being brutally beaten last month at a bus stop in downtown Portland, Oregon, authorities said Tuesday. (Family via Portland Police Bureau)

The suspect, identified as 29-year-old Keffer J. White, was immediately arrested at the scene.

First responders rushed Pierce and the other victim to a local hospital. Pierce suffered critical, life-threatening injuries while the 88-year-old man’s injuries were considered serious but non-life threatening. The 88-year-old has since been treated and released from the hospital.

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White has remained in custody at the Multnomah County Detention Center on two charges of second-degree assault and an outstanding warrant.

Police said homicide detectives have taken the case and additional charges are pending against White.