Const. Kevin Goodmurphy said the man police are seeking boarded the Surrey Central-bound bus on 168 Street and Fraser Highway at around 11 p.m. PT.
"This man was wearing headphones and was reportedly singing, rapping, swearing loudly and intimidating other passengers," he said.
Once the bus arrived at Surrey Central SkyTrain Station, the driver asked the man to stop swearing.
The man then allegedly lashed out at the bus driver.
"[He] punched him the face, took his glasses and ran off the bus," Goodmurphy said.
"The bus driver ran after this man, at which point the man turned around, punched the driver a second time in the face.
"The driver retreated to the bus, was followed by this man, who punched him a third time in the face and ran towards SkyTrain," he said.
The suspect took off his tracksuit jacket, baring his chest, and jumped on a SkyTrain and got away.
The union representing Coast Mountain bus drivers said the bus driver suffered bruises and cuts to his face, and was shaken by the experience.
Nathan Woods, speaking for Canadian Auto Workers Local 111, says the union wants a larger police presence around SkyTrain and buses, and is also offering a substantial reward for information that leads to an arrest, charges laid, or a conviction.
"It's triggered the same way as Crime Stoppers rewards will be," he said. "It's $15,000 or up to $15,000 and it's based on whether there is a conviction or not."