Dozens of members of Congress sent a letter to Attorney General Jeff Sessions on Monday asking whether the Justice Department can prosecute and punish climate change activists who seek to sabotage the nation’s oil and natural gas pipelines.

“While we are strong advocates for the First Amendment, violence toward individuals and destruction of property are both illegal and potentially fatal,” states the letter, led by Rep. Ken Buck, R-Colo. “Recent incidents of individuals attempting to shut down lines by turning valves at pump stations illustrate the danger.”