Twenty-one activists were arrested in Vancouver, Wash. on Saturday in a protest calling for a permanent moratorium on shipping oil by rail in Oregon and Washington, to protect people and the environment.

Approximately 100 protesters took part in the event, blocking trains along the Columbia River gorge. The protest followed the derailment of an oil train in the gorge on June 3 that erupted in flames, spilled 42,000 gallons of crude oil and forced hundreds of people to evacuate their homes.

The crash came three years after a derailment in Lac-Megantic, Quebec that killed 47 people in July 2013.

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“It’s really important communities stand up and stop oil by rail because these trains are so unsafe,” said Mia Reback, a community organizer with Portland Rising Tide and 350 PDX! who took part in the event.

The derailment occurred 70 miles upstream from Vancouver on the opposite side of the river in Mosier, Oregon.  Since then, Union Pacific, which owns and operates the tracks on the Oregon side of the river, voluntarily suspended oil-by-rail shipments through the gorge temporarily. On June 6, Oregon Governor Kate Brown and state lawmakers called on federal transportation officials to place a moratorium on oil train traffic in the gorge until they can determine what caused the derailment.

A letter from H.A. Gard of the Oregon Department of Transportation to federal rail administrator Mark Daniels on June 8 said preliminary results of an investigation suggest faulty bolts that connect the rail to underlying railroad ties was the cause. Gard also called on the U.S. Department of Transportation to impose a ban on all oil trains in Oregon until the cause of the bolt failures is understood.

The Federal Railroad Administration said its investigation of the derailment remains ongoing. “If FRA finds that railroads need to make operational changes, we will direct them to do so,” FRA spokesman Matthew Lehner said in a statement.

The derailment and subsequent protest come as energy companies Tesoro Corporation and Savage Companies are seeking approval to build  the largest crude oil shipping terminal in North America in Vancouver, according to environmental group Earthjustice. The $210 million terminal would ship 360,000 barrels of crude oil per day from trains coming down the Columbia River gorge. The facility is one of several proposed rail-to-tanker terminals in the state spurred in part by the federal government’s recent lifting of a ban on exporting U.S. oil. 

“There is an onslaught of proposed oil-by-rail terminals in Washington that has really become one of the hot-button issues in our state,” said Kristen Boyles, an attorney for Earthjustice. 

The proposed facilities would add six to nine additional oil trains, each pulling approximately 100 tanker cars per day along the Columbia River gorge, Boyles said. Approximately three oil trains carried crude oil from the Bakken oil field in North Dakota down the river gorge each day prior to the June 3 derailment, according to Eric de Place, policy director of the Sightline Institute, an environmental think tank based in Seattle.

A new set of federal regulations were made final in May 2015 aimed at making oil by rail safer, ordering that the oldest railway cars be phased out, new braking systems be installed and mandating lower speed limits through urban areas. The industry complained that the changes were too expensive and activists argued they did not go far enough to ensure safety.

Boyles, who represents opponents of the proposed Vancouver transfer facility, said the crash near Mosier brought the issue home for local residents.

“I’m not sure we needed any more evidence that this possibility could happen since there had been plenty of other accidents across the nation showing the horrifying,  propensity of this oil to explode and catch fire when there is a train derailment,” Boyles said. “But we had it right next door to where this proposal is being now vetted.”

The protesters said oil by rail along the Columbia River gorge should stop not only out of local environmental and safety concerns but also out of concern for climate change. The argument is that such infrastructure projects encourage higher U.S. production of oil and could boost world supplies for years.

“In December, at the Paris climate talks over 190 countries came together and set an agreement to limit global warming,” ideally to 1.5 degrees Celsius, Reback said. “However none of the policies laid out at the Paris climate talks get us anywhere near that goal, and communities are rising up to fill that gap.”