Both directions of Interstate 80 in Berkeley were brought to a standstill by hundreds of protesters Monday night, snarling traffic for several miles, authorities said.
Shortly before 9 p.m., several hundred people climbed onto the freeway near the University Avenue exit, California Highway Patrol Officer Daniel Hill said.
Protesters gained access to the freeway by climbing over fences after the CHP shut down the University Avenue exit ramps, Hill said.
It was the second time Monday night that throngs had blocked traffic. About 8 p.m., at least 100 people stood on the roadway, but officers corralled protesters and moved them off the freeway, CHP Officer Damian Cistaro said.
The protest began about 5 p.m. more than two miles away near the edge of the UC Berkeley campus, Hill said. Protesters marched through downtown and headed down University Avenue toward the freeway.
"We just had reports that a large group was coming toward our station. It was preemptive," Lopez said.
It was the third consecutive night that crowds gathered in the city, protesting the killings of unarmed black men by law enforcement in Missouri and New York.