Police denying it.
The sheriff's office suggested in a statement Monday that an explosion heard during the skirmish might have been caused by small propane tanks that authorities said protesters had rigged to explode.
Dallas Goldtooth, a protest organizer with the Indigenous Environmental Network, did not immediately respond to a request for comment Tuesday. Wayne Wilansky disputed the claim by authorities, saying "there's multiple witnesses and my daughter, who was completely conscious, said they threw a grenade right at her."
The North Dakota Highway Patrol in a statement Tuesday backed up the sheriff's office's version of events, saying officers during the skirmish spotted protesters with "multiple silver cylinder objects."
"It was at this time an explosion occurred and several protesters ran to the area, pulled a female from under the burned vehicle, and fled the scene," the patrol said.
Officers who investigated found 1-pound propane tanks "including one that appeared to be intentionally punctured," the agency statement said.
apnews.com/7fe0b7af0704467eac22b76244ac1982/Pipeline-protester-seriously-injured;-conflicting-accounts
*Edit: added a bit more from the article.