Police said a teen allegedly shot and killed his friend by mistake early Sunday in Billings, Montana when the victim tried to wake him up by throwing pebbles at his window, according to television station KHQ.

At about 2:30 a.m., Mackeon Schulte, 15 and another boy showed up at the friend’s house, KHQ reported.

Police said the 17-year-old inside, whose name was not released, was startled and fired a gun through his bedroom window and hit Schulte in the head, according to the Associated Press.

“When their friend awoke, he was startled by the noise and saw faces outside the window,” a police statement said, according to the Associated Press. “He didn’t know who they were and was scared.”

Police made no arrests and met with prosecutors to decide whether to rule the death a homicide, according to the AP. Investigators also plan to meet with Schulte’s family before going forward, the AP reported.

Authorities did not release the name or age of the uninjured friend.

h/t Gawker

Correction: This post has been updated to show the incident took place in Billings, Montana.