MORTON COUNTY, NORTH DAKOTA — The father of a woman protesting the Dakota Access pipeline says her arm was severely injured by a concussion grenade thrown by police during clashes at 4:30 a.m on Monday.

Lawyer Wayne Wilansky said the grenade exploded at his daughter Sophia’s left forearm, in a statement posted by the Standing Rock Medic & Healer Council.

The blast destroyed all of the muscle, soft tissue, nerves and arteries between the elbow and wrist, and some of the bone. It’s unknown if doctors can recover complete functional use of the limb.

According to the Los Angeles Times, police denied using grenades, instead suggesting Wilansky may have been injured by propane bottles made by protesters.

In another incident, on Monday at 3 a.m officers noticed two men and a woman behind a barricade near a burned vehicle left over from a previous clash on Backwater Bridge.

According to local TV station Valley News Live, they didn’t comply with police orders to come out, so officers opened fire with non-lethal rounds in an effort to force them out.

Police saw more people approaching the area, including someone rolling silver cylinders. It was here police saw an explosion, reported Valley News Live. The protesters then reportedly pulled a women from underneath the burned vehicle.

On investigation of the area authorities discovered propane tanks rigged as improvised explosive devices, slingshots, and rocks.

Police are investigating if the explosives are related to injuries suffered by a female protester, reported Valley News Live.

Activists began protesting the Dakota Access oil pipeline earlier this year out of fears it will impact local drinking water. There were outbursts of violence late last month as protesters clashed with police clad in riot gear.

Activists began protesting the Dakota Access crude oil pipeline earlier this year out of fears it will impact local drinking water. There were outbursts of violence late last month as protesters clashed with police clad in riot gear.