DOVER, Del. — More than six months after a deadly inmate uprising and hostage-taking at Delaware’s maximum-security prison, law enforcement officials appear to be nearing the end of a criminal investigation.

A spokesman for the attorney general’s office said in an email Monday that prosecutors expect to present an indictment to a New Castle County grand jury for consideration within the next 90 days. Meanwhile, prosecutors and investigators will continue to gather evidence.

Delaware State Police are investigating the Feb. 1 uprising, which set off a nearly 20-hour standoff during which correctional officer Steven Floyd was killed. The siege ended when tactical teams used a backhoe to breach the building and rescue a female counselor. Two other guards had been released earlier after being seized, tormented and beaten by inmates.