Police in Swissvale said residents should be on the lookout for burglars posing as water company employees.
Investigators said an elderly couple in the Swiss Helm Park area became the most recent victims.
Police said three men told the couple that they were with the area's water company and needed to check their water lines. When the homeowner asked for identification, the victim said one of the men showed them some type of badge.
Once inside, police said two of the thieves distracted the couple while a third stole thousands of dollars in cash.
Police said the victims had just returned from the bank.
Investigators said they are now looking at bank surveillance video to see if the thieves followed the couple home.