The Philadelphia police are asking for the public’s help in finding an 11-year-old boy who went missing while visiting the Kimmel Center Arts Fest with his mom on Saturday.

The boy, identified as Isaiah Kelvas is white, 4 feet, 8 inches tall, and weighs around 71 pounds, police said.

According to police, Kelvas was last seen wearing a blue Phillies City Connect hat, a blue T-shirt with a New Balance logo, tan Adidas shorts with white stripes, white socks, and charcoal Adidas slip-on sneakers. He was also carrying a brown bookbag.

Pictures taken of him earlier on Saturday are below:

Kelvas was last seen at the event before wandering out the Spruce Street exit at around 12:45 p.m., police said.

Police say Kelvas is familiar with the Center City area and the regional rail line that goes to his home at the 200 block of West Gorgas Lane.

Anyone with information or sees Kelvas is urged to contact the Central Detective Division at 215-686-3093 or dial 911.