Police said Wednesday they had arrested two teenagers and charged them with murder over a Sweet 16 birthday party shooting in a small Alabama town that left four people dead and 32 injured.

The weekend violence in the tight-knit community of Dadeville in the US South was only one of several mass shootings in recent days to plague a nation that is awash in firearms and endures tens of thousands of shooting deaths every year.

The Alabama Law Enforcement Agency (ALEA) identified the suspects, arrested late Tuesday after three days of investigation and manhunts, as Ty Reik McCullough, 17 and Travis McCullough, 16, and said they were each charged with four counts of "reckless murder."

The suspects are from Tuskegee, a town some 30 miles (48 kilometers) south of Dadeville.

Despite being minors the pair will be prosecuted as adults, District Attorney Mike Segrest said, noting that four victims who remain hospitalized are in critical condition.

"We're going to make sure every one of those victims has justice, and not just the deceased," Segrest told reporters.

State and local officials had been facing criticism from the public for failing to release critical details about the violence for days, including whether any suspects were on the loose, or had been killed or wounded in the gunfire.

Authorities have still given no information about the shooters' possible motive for the deadly rampage, whose dozens of victims were mostly in their teens.

After the arrests, ALEA Sergeant Jeremy Burkett pleaded for members of the public who were at the party, at a rented dance studio in Dadeville, to have the "personal courage" to tell police what they witnessed.

Among those killed was 18-year-old Philstavious Dowdell, whose sister was celebrating her 16th birthday on Saturday.

Dowdell was an accomplished high school athlete who had received a scholarship to play football at Jacksonville State University.

The party turned violent when the birthday girl's mother told guests that she had learned people were armed and asked them to leave, according to local media reports.

America's gun violence epidemic has shown no signs of easing. The Alabama shootings came just days after a bank employee killed five people in his place of work in Kentucky.

There also has been a series of shootings in which people were shot after mistakenly ringing the wrong doorbell, approaching the wrong house, or entering the wrong parked car.