Why Didn't They Use Their Resources to Capture Mabhouh?

So it looks like Interpol and various European governments are spending a lot of resources (including putting the 11 suspects on the most wanted list) on investigating the killing of the Hamas terrorist, Mahmoud Abdel Rauf al-Mabhouh. My question is, why are they spending so many resources on this, while they probably never lifted a finger in trying to actually capture him, despite the fact that he likely was involved with the murder of two Israeli soldiers. I guess they really want to punish Israel for ever lifting a finger in its own defense.