The man who founded the whistleblowing website WikiLeaks has defended its actions.
Julian Assange said WikiLeaks - which two months ago released tens of thousands of US military files about the conflict in Afghanistan - worked to protect innocent people.
The UK and the US condemned the leak of classified documents, but Mr Assange denied he did anything wrong.
In a debate at London's City University, he said: "We do not have a goal of having innocent people being harmed. We have exactly the opposite goal. Our goal is to have those people protected."
When asked if he had contemplated the possible danger the publication would cause to Afghans named as helping the US, Mr Assange said: "Of course we considered that. We put in a process of dealing with that. We took away one in five documents prior to the release."
But he added: "That doesn't mean that the process is infallible."
Mr Assange refused to be drawn on the details of the method used, leading some members of the audience to shout "answer the question".
The publication of secret records giving a day-by-day account of Nato forces' operations from January 2004 to December 2009 alarmed the military. The 91,000 classified records revealed new details about the extent of Afghan civilian casualties, a covert special forces unit targeting insurgent leaders, and concerns that Pakistani intelligence could be supporting the Taliban.
Mr Assange used the debate, entitled "Too much information? Security and censorship in the age of WikiLeaks", to defend his organisation. He said: "We don't maintain a philosophy of publish and be damned. Rather, we maintain a philosophy of trying to achieve justice.
"Now, in trying to achieve justice, we are not scared to be criticised. We are not scared to make mistakes."