A semi-detached house in Cricklewood has this week been labelled a sophisticated "charitable front" with links to Al-Qa'ida.

The two-storey building in Anson Road is the registered office of Sanabel Relief Agency, a charity which had its Manchester and Birmingham offices raided by anti-terrorist police last Wednesday.

Sanabel, which also goes under the name of Al-Rahama Relief Foundation, was set up in 1999 and describes itself as "an Islamic charity which aims to relieve Muslims in destitute parts of the world".

But according to a document released by the United States Treasury Department, its main priority is to raise funds for the Libyan Islamic Fighting Group (LIFG), an organisation closely associated with Osama Bin Laden, which was involved in planning and facilitating the Casablanca bombings of May 2003 that claimed 42 lives and injured more than 100 people.

The attack on Morocco's commercial capital saw suicide bombers simultaneously detonate bombs at restaurants, hotels and a Jewish cultural centre on the seafront.

Before September 11, 2001, Sanabel also had an office in Taliban-ruled Kabul in Afghanistan, where the former head of the group had ties to the LIFG. He was later believed to have been arrested in Pakistan with three other LIFG members and Abu Zubaydah, the Al-Qa'ida "number three", according to the US State Department.

The Anson Road address is the registered office for Sanabel in the UK, and Land Registry documents reveal that the property is owned by Mohamed Ahmed Kagzi. Mr Kagzi is also the group's registered auditor, based at offices in Deans Lane, Edgware, according to a copy of the group's accounts lodged at the Charity Commission. He is not one of the individuals listed in the US report.

A neighbour of Mr Kagzi, who did not want to be named, said she was surprised at that news, but added: "You never know, anything could be a front for anything."

Mr Kagzi was not at his home on Wednesday morning, and declined to comment when contacted over the phone.

According to the charity's accounts, approved in October last year, Sanabel donated £16,000 to good causes, including £3,500 to a mosque in India for roof repairs and construction of new facilities, and £1,800 to Qurbani, a charity which helps Palestinian and Lebanese refugees from Beirut. In February, Sanabel's assets were frozen by the UN after the US decision to label them a front for a terrorist organisation.

Last week's raids took place in London, Bolton, Birmingham, Middlesbrough, Liverpool and Manchester. The Cricklewood address was not targeted.

Three people were held under the Terrorism Act. Five were arrested under immigration legislation, including, it is understood, Tahir Nasuf, 44, a trustee of the charity, who was detained in Manchester.

According to the US, Nasuf as well as the British residents Abd Al-Rahman Al-Faqih, Ghuma Abd'rabbah, Abdulbaqi Mohammed Khaled and Mohammed Benhammedi all have links to LIFG.

Patrick O'Brien, the US Treasury's assistant secretary for terrorist financing, said in the report published in February: "The Libyan Islamic Fighting Group threatens global safety and stability through the use of violence and its ideological alliance with Al-Qa'ida and other brutal terrorist organisations. Through a sophisticated charitable front operation and other companies, the individuals designated today have financially supported LIFG's activities."

LIFG emerged in 1995, formed by Libyans who had fought the Soviets in Afghanistan, and was aimed at overthrowing the Gaddafi regime and installing a strict Sharia-based government.

But the movement then embraced the global jihadist agenda of Al-Qa'ida, according to the US State Department, and some senior members of LIFG are believed to belong or have belonged to Bin Laden's senior command structure.