The widow of Mohammad Sidique Khan, the leader of the July 7 suicide bombers, was among four people held yesterday in a coordinated series of raids linked to the terrorist attack on London.

Hasina Patel, 29, and her brother, Arshad, 30, were arrested in West Yorkshire and taken to the Paddington Green police station in Central London for questioning about the 2005 bombings, in which 52 innocent people died.

Also detained yesterday were Khalid Khaliq, 34, from Leeds, who was a close associate of two of the bombers, and 22-year-old Imran Motala, from Birmingham.

The early morning raids, led by the Metropolitan Police counter-terrorism unit, were supported by police officers from the West Yorkshire and West Midlands forces.

All four suspects were being held on suspicion of the commission, preparation or instigation of acts of terrorism. The arrest of Mrs Patel and her brother stunned friends and family in their home town of Dewsbury, where she has been regarded as an innocent victim of the 2005 atrocity.

The former teaching assistant married Khan in 2001. They had one child and Mrs Patel was four months pregnant when her 30-year-old husband blew himself up — murdering six commuters — on an Underground train at Edgware Road station.

Mrs Patel suffered a miscarriage soon after the bombings as she and her mother, a respected local community worker, were forced to go into hiding.

Farida Patel, 67, had received an award at Downing Street and an invitation to a Bucking-ham Palace garden party in recognition of her bridge-build-ing work between different faith communities.

She was said to have been devastated and deeply ashamed by her son-in-law’s role in the July 7 bombings and had only recently returned to live with her daughter at a new address in Dewsbury.

The Bishop of Pontefract, the Right Rev Tony Robinson, knows Mrs Farida Patel through their joint membership of a local interfaith council. He said he had met both Hasina and Arshad Patel and described them yesterday as “very polite, very friendly: a delightful family”.

Friends have always maintained that Hasina and her family — who were from a Gujarati Indian background, while Khan’s family roots were in Pakistan — knew nothing of her husband’s terror plot.

A source close to the family said yesterday that the couple were close to separating before the London attack. As Khan’s views became increasingly radicalised he is said to have become violent at home.

“She was in an abusive relationship. They may have been cohabiting, but to all intents and purposes they had become estranged in the months leading up to 7/7,” the source said.

Hasina’s terrace home in Dewsbury, near a large mosque that is the European headquarters of the Tablighi Jamaat, an Islamic missionary movement, was one of two in the town searched yesterday by police.

Her brother’s rented council house in nearby Batley was also under police guard and two cars, a silver Toyota and a blue Honda, were later driven away by officers. Two addresses in the Beeston suburb of Leeds, which are home to Khalid Khaliq and his parents, were also under police guard.

Mr Khaliq was among a group of Muslim friends — including Khan and Shehzad Tanweer, another of the London bombers — who went on a whitewater-rafting trip in Wales a month before the bombings. He was also a volunteer worker at Iqra, a radical Islamic bookshop in Beeston that was frequented by Khan and Tanweer and is said to have been used to indoctrinate young Muslims to the jihadist cause.

Mr Khaliq, a single parent, was questioned soon after the 2005 bombings but was released without charge. He later told The Times that he had “absolutely no connection” to the suicide plot.

Mr Motala, the fourth person arrested, was detained when police raided a hall of residence used by students of the University of Birmingham, where he is believed to have been visiting his girlfriend, a third-year medical undergraduate.

The arrested man’s family home in the Handsworth area of the city was also being searched by counter-terrorism officers. He is understood to be a relative by marriage of the Patel family.

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