WATFORD CITY -- An FBI agent was shot near here Monday evening while assisting in a widespread drug investigation on and around the Fort Berthold Reservation.

The Minot-based agent suffered non-life-threatening injuries and was treated and released at a local hospital, FBI spokesman Kyle Loven said. Loven said he believes the agent, who was not identified, was back on duty Wednesday.

A suspect, Randy Skarda, was arrested by the McKenzie County Sheriff's Office but had not been charged in connection with the wounding of the agent.

"I wouldn't presume the person would be facing charges for shooting," Loven said.

A shooting team with the FBI is investigating the incident, said Loven, who said he could not discuss details of what occurred.

U.S. Attorney Tim Purdon said federal agents made multiple arrests Monday as part of phase two of a drug investigation called Operation Winter's End.

Purdon said he could not comment further on the arrests made Monday. Phase one of Operation Winter's End involved federal charges against 22 people for conspiring to sell heroin and other drugs on the reservation.

Federal and tribal law enforcement officers working in the Oil Patch have heightened concerns about danger, Purdon said.

"Obviously we're in a very serious battle against drug trafficking organizations that are moving into the area," Purdon said. "These folks are risking their personal health and safety and their lives when they go to work every day."

"It sure seems like every time these federal agents go through a door, pull somebody over, make a move in these investigations, we're seeing more and more firearms, we're seeing higher and higher amounts of drugs," Purdon said.

Skarda, 52, Keene, has citations filed in McKenzie County District Court for possessing a short-barrel rifle and drug charges, including possession of methamphetamine and marijuana with intent to deliver.

Skarda was arrested east of Watford City, but not on the Fort Berthold Reservation, Loven said.

Skarda appeared in court Wednesday and bond was set at $100,000.

Loven said Skarda also was slightly injured during the incident. Loven said he couldn't elaborate other than to say the injuries were not life-threatening.

The federal investigation took place despite the government shutdown. Loven said he wouldn't comment on the shutdown.

Purdon said federal agents are "operating right now with no guarantee when they're going to get paid."

Purdon said while law enforcement officers deserve respect every day for the danger they face, it frustrates him that those officers are taking risks without knowing when they'll be paid.

"That saddens me," Purdon said.

As a result of the shutdown, Purdon said his office is now fighting drug trafficking with half of its staff.

"We're fighting with one hand tied behind our back," Purdon said.