How to remove the values from the many to many relations

Hi all,

I have relation created between product and pointofService, I have some entires there, for source and target, I wanted to remove them programatically, from the class, could you please let me know how to do that ?

         <deployment table="Prod2PosRel" typecode="15003" />
         <sourceElement type="Product" qualifier="product" cardinality="many">
             <modifiers read="true" write="true" search="true" optional="true" />
         </sourceElement>
         <targetElement type="PointOfService" qualifier="pos" cardinality="many">
             <modifiers read="true" write="true" search="true" optional="true" />
         </targetElement>
     </relation>