Livermore police want the public to take a good look at the composite sketch released. He is believed to be around 13 years old and what he did has investigators dumbfounded.
Police say it was on a path near the Arroyo Mocho Creek where he approached an 89-year-old woman. He told her his name was "Cameron," that he was in the seventh grade and that he wanted to show her something off the trail.
She followed him and that is when he struck her on the head with an unknown object.
The boy continued to hit the woman even after she fell down.
"It seems awfully young, but he must have a lot of issues to take it out on an older person like that," said Livermore resident Stevie Lindh.
Luckily, a man ran over after hearing the woman's cries for help. The boy immediately took off on his scooter. Police say they have no idea what motivated him to attack.
The 89-year-old woman was taken to the hospital. She suffered injuries to the head, but has since been released and is expected to be OK.
The people of Livermore now hope police will find the person responsible soon. They say they'll be extra vigilant until the boy is caught.
"That's very unusual for this area and... our group is definitely going to be out here keeping an eye," says Livermore resident Mercedes Phillips.