At least four people were killed and 20 others injured early Sunday when gunfire erupted during a crowded gathering at a bar on St. Helena Island, South Carolina, according to law enforcement officials.

The Beaufort County Sheriff’s Office said deputies responded to reports of a shooting around 1 a.m. at Willie’s Bar and Grill on Dr. Martin Luther King Jr. Drive.

When deputies arrived, they found a large crowd of people, several of whom had sustained gunshot wounds.

A preliminary investigation found hundreds of people were at the bar when gunfire broke out, sending victims and witnesses scrambling for safety in nearby businesses and homes, officials said.

The outside patio area of Willie’s Bar and Grill after at least four people were killed and 20 people injured in a shooting. (Lewis M. Levine/AP Photo)

“This is a tragic and difficult incident for everyone,” the sheriff’s office said in a press release. “We ask for your patience as we continue to investigate this incident. Our thoughts are with all of the victims and their loved ones.”

Anyone with information about the shooting is encouraged to contact the lead investigator, Master Sergeant Duncan, at 843-255-3418. Tips can also be shared anonymously through Crime Stoppers at 844-TIPS-BFT (844-847-7238) or online at tipsbft.com.