Four people have been arrested in connection with a deadly shooting that killed six people in rural Mississippi over the weekend, the F.B.I. announced on Monday.

Three of the suspects — Morgan Lattimore, 25; Teviyon L. Powell, 29; and William Bryant, 29 — were arrested on charges of capital murder, according to the F.B.I.’s field office in Jackson. A fourth person, Latoya A. Powell, 44, was arrested on a charge of attempted murder, officials said.

“Other arrests are pending as this investigation continues,” the F.B.I. said in a brief statement on Monday night that did not include any more details about the investigation. It was unclear if any of the four people arrested had legal representation.

The shooting took place around midnight on Friday in Leland, a town in the Mississippi Delta with fewer than 4,000 people, as a large crowd celebrated homecoming weekend at the intersection of Fourth Street and Main Street. It appeared to have been set off by a disagreement among several people, according to the F.B.I.

The Jackson field office released photos late Sunday of three men and a woman shown in surveillance video and identified at the time as “unknown suspects.” It also set up a website seeking tips from the public.

The shooting in Leland was the deadliest of three attacks that took place in small towns across Mississippi between Friday and Saturday and that left at least eight people dead and others injured. The other two shootings took place on public-high-school campuses that were hosting football games in Heidelberg and Rolling Fork.

Homecoming is a particularly celebratory time in much of rural Mississippi during the heart of football season. The spate of shootings led residents and local officials to decry the region’s strong gun culture and problems with gun violence.

The six people killed in Leland were Oreshama Johnson, 41; Calvin Plant, 19; Shelbyona Powell, 25; Kaslyn Johnson, 18; Amos Brantley, 18; and JaMichael Jones, 34, according to the Washington County’s coroner’s office.