But some intelligence experts have already said they think it's unlikely that the brothers would be there together.
Mosul is in an area of Iraq where they wouldn't have been expected to be in, and by staying together they increased the chances of being found.
If Uday and Qusay have been killed, it's very important for the coalition forces still in Iraq.
Both US and UK troops have been attacked in recent weeks by Iraqi people who still support the old regime.
If those Iraqis see that such important people have been killed or captured, they may be less likely to attack coalition soldiers in the future.
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