CLAYTON, Mo. – Armed suspects robbed two mail carriers Tuesday morning in Clayton and north county, police say.

U.S. Postal Inspectors are working with the Clayton Police Department and other agencies to investigate both robberies.

Police report one robbery from around 10 a.m. Tuesday on Ridgemoor Drive in Clayton. A mail carrier parked on the street shortly before a man approached him with a gun. Investigators say the suspect demanded the postman’s keys to access local mailboxes. The suspect later took off with the postman’s cell phone, but no keys.

Clayton police say a similar robbery happened in North St. Louis County shortly after the one in their jurisdiction, though details on that incident are limited. No major injuries were reported in either case.

According to Clayton police, criminals have targeted postal carriers at various points this year in an effort to steal personal mail or checks to deposit fraudulently.

This is a developing story. FOX 2 will update as more information becomes available.