Police in Okinawa plan to serve a fresh arrest warrant on a detained civilian U.S. base worker on suspicion of rape and murder on Thursday in connection with the death of a 20-year-old local woman in April, investigative sources said Tuesday.

Kenneth Franklin Shinzato, a 32-year-old former U.S. Marine, has been initially arrested for allegedly dumping the body of the victim, and Thursday is the deadline for his detention over the initial charge.

The further move is envisioned by the police at a time when the crime has ignited anger among citizens in Okinawa, home to the bulk of U.S. military facilities in Japan, sparking many protests in the island prefecture and sending U.S. and Japanese officials into crisis mode.