:From reliefweb website  
 :2. For use with alteration in print or online 
 :ReliefWeb maps are free material and you can use them in your work. We request however that you delete the ReliefWeb logo upon any modification to the map. Content of your map will be your responsibility. All maps must be credited as follows: “Based on OCHA/ReliefWeb” 
 :therefore if you change the map (say remove Leeds and add Manchester, or just mark Aberdeen on map, you will HAVE TO remove logo.