A flat being searched by police investigating the July 7 bombings is linked to another address used by the terrorists to make explosives, The Times has learnt.

The one-bedroom property in the Harehills area of Leeds belongs to the same family which owns a flat in the Chapeltown district of the city rented by Hasib Hussain, the 7/7 bus bomber.

That second “bomb factory” was discovered six months after police found the terror cell’s main hideout at Alexandra Grove in the Hyde Park area of the city.

The discovery of a third property linked to the bombers and the launch yesterday of a major search operation indicates that, more than three years after the attacks, the police inquiry is still continuing.

The 7/7 attacks killed 52 London Tube and bus passengers and the inquiries in Leeds are being co-ordinated by Scotland Yard’s Counter-terrorism Command.

The current residents of the flat are not linked to the inquiry and are being accommodated in a hotel pending a search that may last for weeks.

Sources said the flat, on Shepherd’s Lane, would be subjected to a painstaking search but cautioned that it would be difficult to discover concrete evidence after the passage of so much time.

Police officers also conducted house-to-house inquiries in the area showing local people pictures of the four bombers - Hussain, Mohammed Siddique Khan, Jermaine Lindsay and Shehzad Tanweer.

The landlord of the property, Wajid Hussain, said his most recent tenants were Polish and he could not recall who the tenant was in the summer of 2005.

“One of my friends rang me this morning, saying my flat was being raided and that it’s linked to London bombings and that’s all I know,” Mr Hussain said.

He said he had never been arrested or questioned by the police in connection with the London bombings.

Mr Hussain, a supermarket owner, is also the landlord of the Chapeltown property which was sealed off by police for nine months.

He told The Times that he had been asked by Khan to rent the flat to a young friend. That turned out to be Khan’s fellow bomber Hussain.

Mr Hussain recalled that Khan told him that Hussain was a practising Muslim and did not like to hear music.

He visited the lodgings only once during the months when Hussain was living there and formed the impression that his tenant was "big, very quiet, not very clever and a bit slow".

He said: "I spent hours and hours helping the police after they contacted me. The new tenant who was living in the bedsit had to be moved out - the police organised a hotel for him - and it took about nine months before they were finished with it.”

"I helped them as much as I could because I felt it was my duty as a British citizen. I totally condemn the London bombings because in my relgion killing innocent people is wrong."

Mr Hussain said that he still found it hard to believe that Khan, a respected youth worker, and Hussain had been involved in the July 7 attacks.

He added: "I can't understand how they had such hatred in them. When the police told me they'd been making bombs in that bedsit, I was horrified. I used to work downstairs sometimes. It was a scary thought."

Deputy Assistant Commissioner John McDowall, head of Counter Terrorism Command, appealed for anyone with information linking Khan and the bombers to the Harehills flat to come forward.

"While it is more than three years since the attacks this remains a painstaking investigation, and as we have previously said we are determined to identify anyone else who knew what was being planned,” said Mr McDowall.

"As a result of our inquiries we are carrying out an extensive search of the flat to determine whether there are any links to the people responsible for the 7/7 attacks.”

The Harehills area has never before featured in the story of the bombings. It is several miles from Beeston, where three of the four bombers had connections.

The four bombers were killed in the attacks but police have always believed they must have had help in planning their attacks and making the explosives. No one has been convicted over the London bombings, but three men from Leeds, accused of conspiring with the bombers, face re-trial early next year.

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