CHICAGO (CBS) — A lifeguard is being credited with foiling one of several iPhone robberies on or near the lakefront on Saturday.

WBBM Newsradio’s Regine Schlesinger reports five suspects – including three juveniles – face charges, following three separate robberies on Saturday, two of them at the Air & Water Show.

A 20-year-old Chicago Park District lifeguard foiled one attempt to steal a phone at Oak Street Beach, when he went after the accused thief – 25-year-old Darrell Griffin – on Saturday afternoon.

Griffin was arrested about 10 minutes after allegedly taking a Lyons man’s phone. The lifeguard chased him to a tunnel leading to and from the beach, where witnesses saw the two fighting. Griffin was charged with robbery.

Three teens also were arrested at Oak Street Beach on Saturday, after a man saw them swipe an iPhone and its case from under a Chicago man’s backpack on his beach blanket.

When officers questioned the boys – two 14-year-olds and a 15-year-old – they found one of them carrying the stolen iPhone in his pocket. All three were charged as juveniles, and face one count of theft each.

A few blocks away, at Michigan Avenue and Superior Street, a restaurant valet chased down 30-year-old Garland Smith, who allegedly stole an iPhone from a Morton Grove man. Smith was charged with felony theft.