A 64-year-old Hilo man has been charged with allegedly sexually assaulting a 32-year-old mentally disabled woman in Puna.

Louis Sardis was charged Saturday with three counts of first-degree sexual assault and two counts of third-degree sexual assault. His preliminary hearing is scheduled for Thursday. A judge granted a motion to reduce Sardis’ aggregate bail to $49,000 from $68,000.

Shortly before 7 a.m. Friday, police responded to a report of suspicious activity inside a large van parked on Melekule Street in a residential neighborhood.

According to a preliminary police investigation, a resident walked up to the suspicious van and saw a man later identified as Sardis sexually assaulting the woman.

Maj. Sam Thomas, spokesman of the Hawaii Police Department, said the witness called police.

Sardis is known to the victim.

Capt. Randall Medeiros of the Hawaii Police Department’s Criminal Investigations Division declined to identify the organization or company the van belongs to.