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."

The letter was signed by 84 House members asking Sessions if the Justice Department stands ready to investigate and prosecute activists targeting the nation's energy infrastructure.

The letter raises security concerns based on an incident last year in which a group of environmental activists attempted to disable pipelines that crossed the border between the U.S. and Canada in multiple states. The trial for one of the activists began last month.

"Even though some activists commit these acts of sabotage to raise awareness about climate change, they only create the serious risk of harm to the environment they claim to care about," the letter reads. The letter points out that some attackers have attempted to use blow torches on pipes, which can cause oil spills and explosions.

The letter follows reports that the number of death threats directed at Environmental Protection Agency Administrator Scott Pruitt has increased. The threats have resulted in the EPA hiring a dozen new agents to beef up Pruitt's unprecedented around-the-clock security detail. Members of Congress are scrutinizing the increased spending of taxpayer dollars on the increased security, according to CNN. The news organization reported Monday that the increased deployment of security personnel will cost $2 million per year. Pruitt's need for security has outweighed all of his predecessors.

"We realize the Department of Justice faces unique challenges when confronting these crimes, including identifying suspects amidst the rural and remote infrastructure across the country," the letter states. "But maintaining safe and reliable energy infrastructure is a matter of national security."

The letter also asks whether the Patriot Act, aimed a protecting the nation from terrorist attacks, and other pipeline safety laws are adequate to protect the energy system.

It asks whether the Justice Department was taking any investigative or prosecutorial actions against the activists involved in the failed October 2016 attack across multiple states.

The lawmakers also want Sessions to explain whether attempts to disrupt pipeline infrastructure qualifies as "domestic terrorism" under the law.