Delroy Grant, the Night Stalker sex attacker who preyed on elderly people during over a 17-year period

Night Stalker Delroy Grant was convicted today of being one of the most prolific and depraved sex attackers in British history.

Police apologised for botched chances to stop the 53-year-old rapist earlier as he was found guilty of preying on the elderly in a campaign of perverted terror lasting 17 years.

Former minicab driver Grant was responsible for some of the most “awful and disturbing crimes” ever investigated at Scotland Yard, senior detectives said.

A jury at Woolwich Crown Court convicted him of claiming at least 18 victims - but it is feared the total may be more than 500.

The conviction brings to a close a massive manhunt that cost tens of millions of pounds and involved hundreds of officers.

Police missed a key chance to stop Grant in 1999 because of a paperwork blunder, it can now be revealed.

Officers mistakenly ruled him out of their inquiry when the DNA of another suspect with the same name was confused with his.

Commander Simon Foy, head of the Met Police’s homicide and serious crime command, said Grant’s conviction lifted a shadow of fear from thousands of pensioners living in south London.

But he added: “We are deeply sorry for the trauma suffered by all those victims and our failure to bring Grant to justice earlier.”

The police chief branded Grant a “perverted, callous and violent individual” who attacked some of the most vulnerable people in society.

His crimes were “some of the most awful and disturbing in the history of the Met,” he added.

“He was also feared by many people living in the same communities and it is not too dramatic to say when he was caught thousands of people in the South East were able to switch out their lights and go to sleep without the dreadful thought they would be preyed upon by Grant.”

Between 1992 and 2009 the masked sexual predator preyed on frail men and women in south London and violated them in their homes, sometimes for several hours.

Many of his victims - aged up to 89 - were blind, deaf or had conditions including Alzheimer’s and Parkinson’s disease.

Grant targeted detached and semi-detached 1930s houses in leafy suburbs, often levering out double-glazed window units with a crowbar to gain entry.

He was a highly-skilled burglar who carried out daytime reconnaissance.

The hallmark of many of his offences was to remove light bulbs, cut telephone lines, then grab his victims with a gloved hand.

He woke terrified pensioners by shining a torch in their eyes before engaging them in conversation.

Grant then subjected his vulnerable victims to humiliating and degrading sexual assaults for a gratification described in court as impossible to understand.

His “stuff of nightmares” crime spree sparked an international manhunt by police.

Officers had been hunting the Night Stalker, under the codename Operation Minstead, since 1998 when two rapes were linked to the same attacker.

Grant, of Brockley Mews, Honor Oak, eluded capture for years as the tally of victims linked to Minstead soared to 203. The offences took place in areas including Warlingham, Shirley, Beckenham, Bromley, Addiscombe, Orpington and West Dulwich.

The sex beast’s luck finally ran out when police swooped on his car in the early hours of November 15 2009.

More than 70 undercover officers, supported by hidden cameras and a helicopter, staked out several streets in Shirley, near Croydon, in an ambitious operation after Commissioner Sir Paul Stephenson called for a “step change” in the hunt.

Grant, a father of 10 and full-time carer for his estranged wife Jennifer, who has multiple sclerosis and is paralysed, refused to discuss his crimes with police.

But he stunned officers by suggesting they should instead speak to his son.

By the time the case arrived in court more than a year later, he had spun a web of lies in an attempt to get off the hook.

Among a string of “almost laughable” explanations at Woolwich was his claim that his ex-wife stored his semen in 1977, then waited 15 years to frame him for the crimes.

Jonathan Laidlaw QC, prosecuting, attacked him during cross-examination for making up “utter, utter rubbish”, saying he would stoop to any level to avoid prosecution.

There were raised eyes among the jurors as Grant even claimed DNA could be seen with the human eye.

Grant, wearing a pinstripe charcoal suit with round neck black jumper, stood motionless in the dock with his head bowed as the foreman of the jury delivered the verdicts.

An elderly victim and several relatives looked on and smiled from the public gallery.

The jury, who had been deliberating for eight hours and 29 minutes, reached a majority of 10 to two on all 29 counts.

Judge Peter Rook said afterwards he was considering a life sentence.

He told Grant: “You have been convicted of 29 offences of the utmost gravity.

“I am not going to sentence you today because there are various matters that the barristers want to put before me.”

Victims may give evidence in court before the sentencing tomorrow morning.

Judge Rook added: “You should appreciate the sentence you receive will be what is called an indeterminate sentence.”

The term will be “very long indeed”, he added.