Police are sending out a warning to holiday shoppers this month, asking them to pay attention to what they are purchasing.

Just this week, several people were arrested for selling counterfeit items.

Rene Castro, 31, was one of several vendors arrested recently for trademark counterfeiting.

According to the police report, Castro was caught selling counterfeit Hello Kitty merchandise as authentic.

Officer Roger Zuniga with the San Antonio Police Department said shoppers should really scrutinize  merchandise before purchasing.

"Some things to look for, for counterfeit merchandise, is if it sounds too good to be true, it probably is," said Zuniga. "Also, sometimes the labeling is off. It's not exact."

Zuniga said other red flags would be if the vendor doesn't charge tax for the item and the location the vendor is selling it at.

In this case, Castro not only broke the law, but he also broke his contract with the Pica Pica Plaza, where police said he was trying to pass off the fake goods.

Imelda Arevalo, Pica Pica Plaza General Manager, said in that contract, it clearly states that vendors are not allowed to sell counterfeit, stolen or unlicensed merchandise.

Arevalo said if they find that a vendor is selling these items, the contract with that vendor will be terminated.

"We don't want anybody coming here and getting a really bad experience," said Arevalo. "So, we do take measures in letting our shop owners know what is expected of them."

For a list of recent stories Stephanie Serna has done, click here.