BUFFALO, N.Y. (WIVB) — Buffalo police say one of their officers was assaulted during an investigation Sunday morning.

Around 4 a.m., an officer was investigating an incident on Pearl St. when he was punched in the back of the head.

Buffalo resident Luis Vargas, 22, was subsequently charged with second-degree assault.

At the same time and place, police say a fight broke out between some people believed to be known to each other.

Three people were cut or stabbed and needed medical attention.

Anyone with information that could help police can call or text their confidential tip line at (716) 847-2255.