Is this a case of copyright infringement?

Is it possible for you tell me if someone has infringed my copyright?

I have produced some logos and designs for a friend (who was acting on behave of the Golf Club as an employee) whilst he worked on a freelance basis for a golf club. The company he worked for refused to pay for the designs and logo. My friend has left that club and now works for a different golf club. The original club is still using my designs and logos for promotional material and their website. They still haven't paid for any of it. I presume they are infringing my copyright?

Hope you offer some initial advice.