Blood loss from hemerroids?

I have had major blood loss from rectal bleeding and wonder if this can be caused by hemerroids?
My hemoglobin was down to 5.7 and hemocrit of 17.9  I was transfused and had a colonoscopy and an endoscopy
as well as swallowed a small camera and the gastrologist found nothing to cause bleeding.
I have started to bleed again and my levels are down to 8.1 and 24 hemocrit  what else could be causeing this?
I have alot of blood when I move bowels. would appreciate any help I could get am going for an abdominal ultrasound tomorrow.  Thanks

[Morecambe]

Rectal bleeding should always be medically investigated until a concrete cause is found.  Type rectal bleeding into google and click on to one of the many sites - the Medicinenet site is especially informative.  Then you will be better prepared for your next medical consultation.  Unless the cause can be identified as one of the minor ones (e.g. anal fissure, haemorrhoids etc etc - and this means a firm diagnosis not a statement such as "well it looks as if it might be .....") then I suggest that you request a colonoscopy.

regards
Morecambe