The driver who fatally hit a runner in a St. Paul crosswalk last week has learned since the crash that he has brain cancer, a friend of the motorist said.

Mike Salovich said that Peter H. Berge has "primary glioblastoma brain cancer," a very aggressive form of cancer. "It is a type that is inoperable and can only be treated by radiation and chemotherapy," Salovich said.

Berge was arrested Feb. 22, a Wednesday, on suspicion of being under the influence of drugs when he ran over 35-year-old Scott Spoo late that afternoon. Spoo was running on Mississippi River Boulevard at Dayton Avenue.

A breath test revealed no alcohol in his system, but Berge failed numerous roadside sobriety tests moments after the crash, according to a search warrant affidavit filed in Ramsey County District Court a few hours after Spoo was hit. Berge told police at the scene that he hadn't taken any illicit drugs or medication, the court filing read.

Police Sgt. Mike Ernster said that if there is more about Berge's health collected by investigators, "we will include all the information" as the inquiry proceeds.

The search warrant affidavit did not address what police said earlier, that Berge was distracted by his cellphone at the time. The filing did say the 60-year-old attorney told police that Spoo "stepped out in front of him and he did not see him."

The search warrant affidavit allowed police to take blood from Berge for toxicology tests.

Results are likely months away, authorities said.

Salovich, a longtime friend of the attorney, said Berge underwent a brain biopsy Monday and had one of four lesions removed.

Berge declined to comment, referring calls to his attorney, who did not return messages.

When Berge was asked about his health immediately after the crash, he "stated he had no physical defects," the search warrant affidavit read.

The first inkling he had that something was wrong with Berge's health came when he was released from jail Friday and began having trouble with fine motor skills.

The search warrant affidavit noted that Berge had "eyelid, body and leg tremors" soon after the crash.

The court filing detailed what led the officer to conclude that Berge appeared "to be under the influence of one or more substances" when he hit Spoo.

The officer, who is a certified drug recognition expert, said Berge failed the standard eye test for sobriety, nearly fell three times, failed another element of the "walk and turn" test and almost fell when directed to stand on one leg.

"I terminated the test for his own safety," the officer wrote.

The officer said he examined Berge's mouth and saw a white residue on his tongue with a green tint that suggested "marijuana residue."

However, Berge said he couldn't recall the last time he smoked marijuana.