A fire hydrant plant in Alabama reopened Monday, nearly a week after a gunman killed two co-workers and wounded two others there, news outlets reported.

Albertville Police Chief Jamie Smith said Monday that investigators still don’t know the motive for the shootings early Tuesday at Mueller Water Products.

“Our detectives have already logged numerous hours investigating and have interviewed numerous people with several more to go,” he said in a message on the department’s Facebook page. “The detectives have even gone to the length of traveling to Chattanooga to Erlanger Hospital last Friday to speak with the relatives of the victims that are recuperating there.”
Chattanooga is about 75 miles (120 kilometers) northeast of Albertville.

Police said last week that Andreas Horton, 34, used a handgun to kill and wound co-workers before dawn Tuesday and was found dead in his vehicle in nearby Guntersville. Police said he apparently had shot himself.

Police identified the dead men as Michael Dobbins and David Horton, both of Boaz. Smith said he believed the Hortons were unrelated.

Casey Sampson and Isaac Byrd, both of Albertville, remained hospitalized.

The company has said it will pay for funerals and help all four families. It started an online survivors’ fund with $100,000, news outlets reported.