Police allege that a Costa Mesa teenager arrested Tuesday pepper-sprayed two men in the face and made off with designer shoes and a backpack in two separate robberies recently in Costa Mesa.

At about 12:15 p.m. Tuesday, an 18-year-old man told officers that he had met with someone who was interested in buying a pair of designer shoes he had advertised on a resale app, police said.

After the would-be buyer inspected the shoes, he pepper-sprayed the seller in the face and fled with the footwear, police said.

During their investigation, police said, officers connected the thief to a similar case May 12.

In that incident, police responded at 12:48 p.m. to a parking lot in the 1700 block of Adams Avenue, where a 24-year-old man said he had met with someone who said he was interested in buying his backpack.

The seller told police that the potential buyer pepper-sprayed him and took off with the backpack, authorities said.

While investigating that case, police identified a possible suspect and obtained a search warrant for his apartment in the 2700 block of Mesa Verde Drive East. The apartment was searched at about 1 p.m. Tuesday.

Matthew Chima Udechukwu, 18, was arrested there on suspicion of robbery, police said.

He was booked into Orange County Jail with bail set at $50,000, according to jail records.

Police are continuing to investigate both cases. Anyone with information is asked to call Det. Jason Chamness at (714) 754-5197.

hannah.fry@latimes.com

Twitter: @HannahFryTCN