Given the extra photo by Andy, I think the wing structure fits Marsh more than Pied (secondary bulge + sharp wing / longer P3). Also, some juvenile Marsh Harriers seem to show barred wings + tail + white rump:
http://orientalbirdimages.org/se ... _ID=&pagesize=1
Albeit the white rump is not as clean as in Pied, perhaps like in the first photo where the rump feathers have a terminal brown band. May the wing/tail barring be variably present in Marsh too? It seems to be the case. I also have a query about the white breast band - this feature seems to be present in many Marsh but I have yet to see a photo showing Pied with this band - they tend to show a pale breast shield at most. So would this bird just be an atypical Marsh rather than a Pied?
It'd be nice to hear more comments from experts!