A serial sex attacker who has raped three women, murdering his last victim, has now been linked to up to eight attacks by detectives leading Britain’s biggest manhunt.

The man always strikes in the early hours of the morning in East London and detectives are convinced that it is only a matter of time before he rapes or kills again.

They have started an unprecedented DNA sweep of residents in 9,000 homes in Walthamstow and brought in geographical profilers to try to narrow down where he could live based on where he offends, and behavioural experts to try and work out where he could strike next.

Sixty murder squad detectives have been drafted in from all over London to work on the investigation, known as Operation Eklutna, as well as dozens of uniformed officers who are patrolling the streets at night.

A police source said: “This is the biggest manhunt going on in Britain. We are desperate to catch this guy as it is extremely likely he will attack again.”

Senior Scotland yard officials have given the go-ahead to keep the expensive operation running but one fear is that the killer has now left the area because of the publicity surrounding his crimes.

So far 435 men matching the description of the suspect have agreed to give their DNA and 13 have refused. Officers say the refusals have been for good reasons, but they will all be looked at closely.

The suspect, who is of Asian appearance, does not match any profile on the national DNA database. One theory is that he is a new arrival to Britain who has previously targeted women abroad as it is very unusual for a criminal to start raping women without committing other, less serious offences first.

The man was linked by DNA to three attacks on women after committing murder. He apparently gained the trust of all three victims during what appeared to be chance encounters in the street.

His first linked victim, 59, was attacked in her home on March 24 after he began speaking to her as she reached her house at 1am. He pushed her inside and beat her before raping her.

On April 22 at 1am he approached a 46-year-old woman as she walked home, asked for directions and then dragged her into a nearby alley as they walked along, where he carried out a prolonged and vicious attack.

Officers believe that this shows local knowledge of the area.

His third victim, Michelle Samaraweera, 35, was last seen on May 30 at 1.15am when closed-circuit television captured her leaving a supermarket with two bags of shopping.

Her body was found in a children’s play area in Queen’s Road, at 5am with her shopping nearby. She had been strangled. Teenagers in the area said that no one had been there at 3am and police are trying to find out where Ms Samaraweera spent the time before her body was discovered yards from a row of terraced houses.

Since the attacks were linked by DNA, police have trawled through hundreds of sexual assaults in the area going back to January to see if there have been any similar attacks.

They have found one possible rape and one indecent assault that they believe was carried out by the same man and three other attacks where the attacker bears a striking similarity to their suspect. They have not been linked by DNA, however.

One was only a week after the 46-year-old woman was attacked.

A senior Metropolitan Police source said: “We cannot be one hundred per cent sure because we do not have DNA to link them but we are convinced as we can be that he is responsible for two other attacks and probably responsible for three others.

“This is a massive operation and we are absolutely desperate to catch this guy before he strikes again.”

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