FREMONT -- Police are asking the public's help in finding an "at-risk" adult who went missing earlier this week.

Jessie Cuevas, 24, was last seen at noon Monday when he walked away from a landscaping job at the intersection of Decoto Road and Paseo Padre Parkway in Fremont, according to police spokeswoman Geneva Bosques.

Cuevas, who lives in San Jose, suffers from a mental illness, Bosques said.

He is a Hispanic man, 5 feet, 10 inches tall,, 145 pounds with brown hair, brown eyes and a beard. He was last seen wearing a white T-shirt, blue jeans and work boots.

Cuevas does not have a vehicle or a cell phone and tends to wander off when he is not taking his medication, Bosques said.

Anyone with information about Cuevas' whereabouts can call Fremont police at 510-790-6800 and select option '3'.

Contact Natalie Neysa Alund at 510-293-2469. Follow her at Twitter.com/nataliealund.