Two people died and at least nine others were injured in a stampede that broke out during a GloRilla concert in Rochester on Sunday night. Attendees were leaving the Main Street Armory venue shortly after 11PM when fears that a shooting had occurred caused people to surge forward.

“We do not have any evidence of gunshots being fired or of anyone being shot or stabbed at the scene,” Police Chief David M. Smith said at a news briefing, adding that they are investigating potential sources of the surge that include “crowd size, shots fired, pepper spray and other contributing factors.”

Two women, ages 33 and 35, died at a local hospital due to injuries sustained during the stampede, WHAM reports. Another 35-year-old woman is in critical condition and additional concertgoers were treated for non-life-threatening injuries.

“I’m just now hearing about what happened wtf,” GloRilla tweeted an hour after the concert ended. “praying everybody is ok.” The Grammy-nominated rapper was performing in Rochester with Memphis rapper Finesse2tymes.