Two Iowa environmental activists who in 2017 admitted to damaging a controversial pipeline are facing charges in federal court.

A federal grand jury on Sept. 19 charged Jessica Reznicek and Ruby Montoya each withone count of conspiracy to damage an energy facility, four counts of use of fire in the commission of a felony and four counts of malicious use of fire, United States Attorney Marc Krickbaum announced Tuesday.

The charges are related to multiple times the pair, in 2017, allegedly damaged the Dakota Access Pipeline in the Southern District of Iowa, and the women's alleged conspiracy to cause up to $100,000 in damages to an energy facility, Krickbaum said.

► Previously:A year later, still no federal charges against 'saboteurs' of Dakota Access Pipeline. Why?

Reznicek and Montoya, who had been involved in the Des Moines Catholic Workers' social justice movement, held a news conference in July 2017 where they described their "direct action" campaign to stop the pipeline while it was under construction.

The two women said their sabotage included burning at least five pieces of heavy construction equipment in northwest Iowa's Buena Vista County.

They also used oxyacetylene cutting torches to damage exposed, empty pipeline valves up and down the pipeline route across Iowa and South Dakota.

They later used tires and gasoline-soaked rags to burn multiple valve sites and electric units, as well as heavy equipment on pipeline easements.

The damage to heavy equipment in Buena Vista County alone was estimated at exceeding $2.5 million, while damage at a series of work sites elsewhere in Iowa after November 2016 was described as either undetermined or for lesser amounts.

Prior to November 2016, before the two women claimed to have begun their initiative, authorities said at least $3 million in damage had been reported on the pipeline project from apparent arson incidents.

The women were arrested by Iowa troopers following their 2017 press conference because they damaged a state-owned sign outside the Iowa Utilities Board's offices. But they faced only minor charges for the sign damage and were fined.

Reznicek and Montoya are scheduled to go to trial on July 20, 2020, at the federal courthouse in Des Moines.

Both women could face decades in prison if convicted.

Anna Spoerre covers crime and courts for the Des Moines Register. She can be contacted at aspoerre@dmreg.com, 515-284-8387 or on Twitter at @annaspoerre.

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