Wednesday marks exactly one month since the murders of three people in Saitama Prefecture. The man arrested in connection with the incident continues to deny involvement.

On December 25, William Bishop Jr., a 69-year-old American citizen, and his 68-year-old wife Morita Izumi were found dead at their home in Hanno City, Saitama along with their 32-year-old daughter Morita Sophianna Megumi, who lived in Tokyo.

Saito Jun, a 40-year-old neighbor of the couple, was arrested on suspicion of killing the two.

Sources familiar with the investigation into the case say the suspect answers questions about his upbringing, but remains silent on the incident.

No items indicating a possible motive or background of the alleged attack have been discovered among objects seized from his home.

But samples of DNA from bloodstained clothes found there matched that of the three victims. Several blunt instruments, including what appears to be an ax, were confiscated from the home.

Police are also trying to determine whether the suspect was involved in killing the daughter.