[otrs] How to close a ticket via PHP and SOAP?

Hi, This is another question related to our application that talks to OTRS. We create tickets via php and soap, but I need to know if there is a similare way to close a ticket when a job (in our case) is finished? I've searched the web, but I mostly see info about how to create a ticket. Anyone knows if and how we can close one via PHP and SOAP? Cheers, Andy