A Black Lives Matter protester died after being struck by a car that drove down a closed stretch of Seattle highway and plowed into demonstrators early Saturday morning, according to hospital officials. A second person hit remains in serious condition as of Sunday morning.

The killing adds to the violent toll of this summer’s protests in Seattle, where at least six people have been shot in the past month in the vicinity of the recently cleared protest encampment.

Summer Taylor, a 24-year-old Seattle resident who works with veterinary clinics, was hit by the car around 1:40 a.m. Saturday while standing with a group of a couple dozen protesters alongside Interstate 5, a primary north-south highway along the West Coast.

Taylor died at Harborview Medical Center in Seattle on Saturday evening, according to hospital spokeswoman Susan Gregg.

A colleague of Taylor’s at the Urban Animal veterinary clinics told the Seattle Times that Taylor had been a frequent presence at protests.

“Summer has been there since day one standing up for black lives, staying out all day and night, while still working full time taking care of animals,” Katelyn Hoberecht said. “Summer talked [to] me about the protests, and how incredible it was to be a part of something so huge — a part of history.”

The second person hit, Diaz Love, 32, suffered injuries and remained in the intensive care unit at Harborview.

In videos captured of the incident and posted online, a white Jaguar can be seen speeding down the wrong way of an exit ramp and onto a closed stretch of I-5. That portion of the interstate was closed by Washington State Patrol as protesters taking part in the Black Femme March had entered the roadway. In seconds, the Jaguar swerves around parked cars and drives directly into the group of a couple dozen protesters. Shouts of “car!” can be heard as the panicked crowd flees. Two people — Taylor and Diaz — were hit.

Police identified the driver as Dawit Kelete, 27, of Seattle. He was arrested and taken to King County Jail on Saturday morning on investigation of felony vehicular assault. Authorities don’t believe Kelete was impaired when he drove into the crowd.

After the incident, the Washington State Patrol wrote on Twitter that it would not allow protesters to enter I-5 in the future and would arrest those who do.

Seattle authorities have taken a firmer stance toward protesters amid a series of violent incidents. Police last week cleared out the protesters who had camped out in the Capitol Hill neighborhood after several shootings.