Eight members of MI6 — including two former heads of the agency — have given secret evidence to the Iraq Inquiry, it has been announced.
Ex-spy chiefs Sir Richard Dearlove and Sir John Scarlett are among 35 witnesses who have appeared before the inquiry.
Another six unnamed members of the Secret Intelligence Service, as MI6 is officially called, also provided testimony.
Several senior British officials have now given evidence in public and private, including former UN ambassador Sir Jeremy Greenstock and Tony Blair's foreign policy adviser Sir David Manning.
Former ambassadors to Iraq Dominic Asquith, Edward Chaplin and Christopher Prentice have also appeared.
Witnesses were allowed to give evidence in private if it related to matters that could damage national security or because of their personal circumstances.
Iraq Inquiry chairman Sir John Chilcot, said: “These hearings have given the inquiry valuable evidence which could have not be heard in public session without damaging national security or international relations.
“They have supplemented the inquiry's understanding as it takes forward its public work.”
The inquiry will today publish transcripts of evidence sessions with junior officials who appeared in private.