Israel’s attorney general and state attorney are working with police and military to formally investigate the Hamas attack on Oct. 7, they announced Wednesday.

“Our goal is to investigate and initiate legal proceedings against those who perpetrated, planned and otherwise took part in these heinous acts -– wherever they are,” the statement said. It said Israel would punish the Hamas militants with “the utmost severity, commensurate with their crimes.”

Police are working to collect evidence from towns across the south as attorneys for the Ministry of Justice decide how best to proceed with the investigation.