A 42-year-old Waianae man is facing charges that he sexually assaulted an underage girl and beat the girl’s brother when the boy tried to stop him.

An Oahu grand jury charged Thomas K. Kamaka Jr. Thursday with four counts of first-degree sexual assault involving a victim under 14 years old. 

The indictment alleges the crimes occurred over the past two months. But Deputy City Prosecutor Vickie Kapp said Kamaka has been sexually assaulting and beating the children for the past five to six years.

When the boy tried to stop Kamaka from assaulting his sister, Kamaka punched the boy on his head and shoulders, kicked him in the ribs and used a drill bit to hit the boy on his arms and head, Kapp said.

Kapp said Kamaka was able to post $150,000 bail after police arrested him last week Friday and charged him with just one sexual assault. 

She asked state Circuit Judge Richard Perkins to increase bail to $350,000 because Kamaka is facing three more sexual assault charges and because she said Kamaka has threatened the children if they told on him. Kamaka has also told the children he will kill their mother, Kapp said.

Perkins kept Kamaka’s bail at $150,000. He issued an order for Kamaka to stay away from the children.