Lawyers estimate that the figure could be this high because of the aggressive nature of the police operation.
Amid fears at Scotland Yard of a “long hot summer of community mayhem”, the Met is understood to be preparing for a six-figure pay-out to Mohammed Abdul Kahar, 23, and Abdul Koyair, 20.
During the raid Kahar was wounded by a shot from a firearms officer’s gun, although the circumstances in which it was fired are heavily disputed.
The two men were released without charge last Friday after a top-level meeting at Scotland Yard decided their detention could no longer be justified.
Sir Ian Blair, the Metropolitan police commissioner, is facing renewed calls for his resignation because of his force’s handling of the incident in which 250 police and MI5 officers, hunting for a chemical bomb laced with cyanide, stormed the brothers’ home.