The civil servant at the centre of the Damian Green leak inquiry has told how his Feltham flat was raided by anti-terror officers.

Christopher Galley claimed police threatened him with life in prison when they burst into his home in Redford Close at 5.30am on November 19 last year.

The 26-year-old junior Home Office worker was arrested and held for 17 hours after leaking documents to Shadow Immigration Minister Damian Green, who was also arrested.

The Crown Prosecution Service (CPS) decided last week not to charge either men for misconduct in a public office.

This week Mr Galley told how he had been woken early on the morning of the raid by banging on his front door.

He said: “I assumed it was a neighbour, come to tell me there had been a flood or something.”

Officers seized computers, phones and documents before putting him in an unmarked police car and taking him for questionning at the specialist Paddington Green station.

Mr Galley said he had leaked four documents because he felt he had to expose inadequacies within the department.

He said: “I did it because what I saw happening was wrong.”

The four documents that he leaked to the press included memos about where illegal immigrants were working and a draft letter from Home Secretary Jacqui Smith about the fear that the recession would lead to a rise in violent crime.

The anti-terror squad had been called to arrest Mr Galley and Mr Green on the grounds of national security. Mr Galley faced disciplinary action for misconduct.

On the news that the CPS had decided not to charge him, he said: “I felt relieved when I found out I wasn’t going to be charged.

“But it has been worth it. Yes, I would do it again.”