当自由翻译者遇到骗子 translating scam

I am a freelance translator and was contacted by a possible client asking if I could translate a document from English into French. We agreed on $850.00 to be paid in three increments. After I completed the first part, they sent me a check for $1,950.00 asking me to deposit it in my account and send a check for the difference to their accountant. I am obviously not going to deposit the check and don't know what to do with it. Has anyone heard of anything like this and what should I do with the check?