At least four people were fatally shot and a dozen wounded late on Friday, in Leland, Miss., which was celebrating homecoming weekend, the city’s mayor said.

The mayor, John Lee, said on Saturday that it was unclear what led up to the shooting. The police have no suspects, he said.

“We’re making every effort to find out who did the shooting,” Mr. Lee said. “My condolences to the family of the deceased. We’re just in prayer right now for our whole city because this is not something we represent here in the city of Leland.”

The homecoming celebrations in the city, which is about 115 miles northwest of Jackson, include a football game at Leland High School, which many people from out of town come into the city for, Mr. Lee said.

People who attended the game gathered afterward near Main Street, where the shooting occurred around midnight.

Mr. Lee said he believed all the victims to be adults and that the wounded were being treated at hospitals.

“This doesn’t normally happen in our city — it’s never happened before in our city,” Mr. Lee said.

The Mississippi Bureau of Investigation said in a statement on Saturday that it was helping in the investigation.

This is a developing story. Check back for updates.