However, the air of normality in this unprepossessing tree-lined street in Birmingham's eastern suburbs lasted until dawn yesterday, when 35 armed police officers arrived at the door of the three-bedroom, semi-detached house. Residents were awoken at 4.30am to the sounds of shouting and banging.
Once inside, officers from West Midlands Police and the Metropolitan Police anti-terrorist branch found Yasin Hassan Omar, 24, who police believe attempted to blow himself up in a packed Tube train at Warren Street station a week ago.
They located him in the bathroom, possibly wearing a rucksack, according to one local police source, and within seconds hit him with a 50,000-volt charge from a Taser gun as he tried to flee. Officers may have feared the rucksack was packed with explosives, although they said later that none had been found at the scene.
Ninety minutes later Mr Omar was led from the house in a paper boiler suit, plastic handcuffs and plastic gloves. Police stopped him briefly in his front garden and searched around his feet before placing him in a police van, which removed him to Paddington Green high-security police station in London for questioning.
Andrew Wilkinson, who lives opposite the house, said: "The guy was in his twenties, and looked Somalian. He bears a striking resemblance to one of the four guys linked to the terror attacks - the one with the darkest skin and curly hair [Omar]." Three minutes later, a Filipino woman was also led away from the property, according to Mr Wilkinson.
At first, five houses were evacuated, though police later extended the cordon and evacuated 100 families for fear that explosives may be in the house.
The trail to Heybarnes Road possibly led from a flat at Curtis House, north London, where Omar has been the registered tenant since 1999, sharing the property with Muktar Said Ibrahim, who police believe tried to bomb the No 26 bus in Hackney, east London.
The pair may have been in Birmingham since Saturday. The Nissan, which as many as four Somalis from Heybarnes Road had ridden around in, reappeared then at 2pm after an absence of seven to 10 days, according to locals. Katy Stewart, 31, who lives opposite the house, noticed the Somalis arriving laden with duvets, pillows and bin liners. "It was always the four guys together, coming and going," she said.
The men Mrs Stewart had seen wore traditional Muslim dress and sometimes fleecy jackets.
An hour after events began unfolding in Heybarnes Road, several dozen officers - many armed and some with dogs - arrived at 59 Bankdale Road, fewer than two miles away.
At 5.20am, postman Keith Batcheltor heard loud bangs, screaming and shouting. "I opened my curtains and there were armed police everywhere. I saw flashes going off in various rooms and smoke in the back garden before they ripped off the front door."
Three young men of east African appearance were led away, handcuffed, into unmarked cars. Forensics officers emerged at 1pm carrying two large sealed bags.
One neighbour, Benia Meen, believed Somali men had lived at the property for eight months but a new group took up residence four weeks ago. Locals said they were "very quiet", though they had occasionally been seen sitting in the garden, drinking tea and smoking flavoured tobacco.
Meanwhile, further details emerged yesterday of Mr Omar's background. A friend said he had lived in the Somali capital Mogadishu and had led a feral existence.
Jamal Mohammed, who met Mr Omar during football games played close to the north London flat raided by anti-terrorist police this week, said the man suspected of carrying out the bombing on the Tube train at Warren Street station had mixed with militiamen during the conflict in Somalia.
Mr Mohammed told The Independent: "Yasin told me where he lived in Mogadishu had been controlled by a militia and he would sit with them as they stopped cars and lorries. "He was only a boy but he said they had fascinated him at the time with their guns. He said once he came here he realised what kind of people they had been. He said he had lived on the streets during the day, getting what food he could. Then his parents managed to send him to Britain."
He added: "I last saw him a couple of years ago ... he had begun to be angry about the West, he would criticise them [over] what was going on in Afghanistan.
It emerged last night that Mr Omar had come to Britain aged 12 with his elder sister and her husband in 1992. All three had lived together initially in Enfield, north London. It is thought a family dispute led to Mr Omar leaving the home and being taken into care by social services. He stayed with a series of foster parents before moving to Curtis House in February 1999.
A 50,000-volt charge that disables suspects
The use of a stun gun on one of the suspected suicide bombers in Birmingham highlights the growing use of the weapon to deal with potentially dangerous offenders.
The M26 Taser gun, which was approved for use in September 2004, packs a 50,000-volt charge that disables a suspect, causing their muscles to contract uncontrollably.
The weapons, which were first used in April 2003, have been given to police firearms officers as a non-lethal alternative to the gun. There is pressure from police unions for all officers to be armed with the stun guns, but earlier this month Hazel Blears, the Police minister, said the weapons were "too dangerous'' to be handed out to all patrolling officers. There have been concerns expressed that it can kill if fired at someone with a heart complaint.
It looks like a pistol but uses compressed air to fire two darts, up to 21 feet, that trail a cable back to the handset. A five-second charge is released down the cable. However, officers have failed to hit their target on several occasions and often the dart does not attach properly.
Despite these problems, the gun seems to have been effective in overwhelming Yasin Hassan Omar who was arrested in the early hours without any members of the public near by. Because a stun gun temporarily paralyses, police believe it would be virtually impossible for a suicide bomber to detonate his device. But there is a risk.
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