Authorities have revealed that a total of four people have been arrested at the Long Island post office where people have complained about check-washing scams.

On Tuesday News 12 learned about the arrest of three men who were allegedly caught in the act by police at the Merrick Post Office on Fisher Avenue.

Police say the alleged thieves even had a key to open the mailbox.

News 12 has learned that another person was arrested for a similar alleged crime on Dec. 5. In that case, the suspect allegedly used a homemade device to go "fishing" for mail in the mailbox.

The United States Postal Inspection Service does not believe the two incidents are related.