As it approaches its conclusion the Saville inquiry has heard that it is still "not in any way clear" who shot the 27 civilians on Bloody Sunday.

On Monday, at the start of two days of summing up, inquiry counsel Christopher Clarke QC told the tribunal that the central issue was still not resolved even though £130 million of public money had been spent on 433 days of evidence.

The investigation established by the prime minister in 1998 under Lord Saville was reaching its end ahead of a final report expected next year.

That will bring the total cost of the inquiry to around £150 million, but Clarke told the three man panel that it had failed to resolve the key questions about who in the military opened fire.

"It has to be said that, even after many days of evidence, the answer to even the first question - who shot them? - is not, on the soldiers' evidence, in any way clear," he said in a summary of up to 10 volumes of written evidence and statements from over 900 witnesses.

The investigation into the events surrounding the civil rights march in Londonderry in January 1972 was set up in response to demands from nationalists and republicans in the run-up to the Good Friday agreement.