Tyler De Martini — the 18-year-old who suffered a critical head injury when he was hit by a car on Marin Avenue while skateboarding — died Wednesday afternoon at 4:10 p.m. at Highland Hospital, according to Berkeley police.

"Members of BPD (Berkeley Police Department) extend their condolences to the De Martini family," police Sgt. Mary Kusmiss said in a news update.

Friends and family members of De Martini had been at his hospital bedside as the young man lay in a coma since the accident Monday night when he was hit by a car while riding his skateboard on Marin Avenue.

Earlier today, friend Gabe Scaglione said De Martini was being kept alive by machines as loved ones spend some last moments with him. Tests for brain stem activity came back negative, Gabe told Berkeley Patch in a message on Twitter.

De Martini was skateboarding west down Marin Avenue about 7 p.m. Monday night when he was hit a Prius going eastbound on Marin that was turning onto Tulare Avenue, Berkeley police said. He was not wearing a helmet and had an obvious head injury, according to police and witness accounts.

Sgt. Kusmiss added additional news with some reluctance:

"Although difficult to share, the BPD preliminary collision investigation has determined the PCF — Primary Collision Factor — as 'a pedestrian in the roadway.' Skateboarders are considered pedestrians in the CA Vehicle Code. Pedestrian on Roadway CVC 21956.  (a) No pedestrian may walk upon any roadway outside of a business or residence district otherwise than close to his or her left-hand edge of the roadway."

Earlier today, Albany mom Amanda Azevedo said her daughter went to Highland Hospital to see Tyler. She shared, on Facebook, that her daughter called her crying at about 2:30 p.m., saying Tyler "passed away before they got there." 

Friends and family members have been sharing additional information. 

Scaglione's mom, Janet, wrote via email to Patch that a number of kids were at the hospital writing notes to Tyler. 

Azevedo said her daughter went to Highland "with a few close friends; they're all still together. I told her she could be with them for a while, to talk and cry and be together."

De Martini was the second East Bay young man to die from a head injury caused by a skateboarding accident in the past week. On Sunday, Tucker Hacking, 20, of Walnut Creek died after a skateboard accident in Lafayette Friday. Hacking, who hit his head after falling from his board on a steep road, was not wearing a helmet, according to the Contra Costa Times.

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