A rapist who reigned terror over the elderly of south London was finally caught after he became too greedy.

Delroy Grant, dubbed the Nightstalker after committing hundreds of burglaries, in some of which the victims were raped and sexually assaulted, was finally caught when he changed his motive.

The gerontophile, who targeted elderly men and women who lived alone, changed his tactics soon after a county court judgement was lodged against him for £20,000.

He operated around various locations in south London but predominantly targeted Shirley in Croydon because of its large elderly population.

The twisted burglar started his reign of terror in 1992 and acted with impunity up until 2009, despite hundreds of officers and millions of pounds being spent trying to catch him.

A shift in the investigation in 2009, after he switched from gaining sexual gratification from his crimes to a more money-driven motive ended in his capture.

In early October 2009, just one month before prime suspect Grant, 53, was arrested in Shirley, Detective Superintendent Simon Morgan was taken off the investigation.

Det Supt Morgan was replaced by Detective Chief Inspector Colin Sutton - the officer responsible for the operation which caught serial killer Levi Bellfield.

The operational strategy took on a completely different focus, where DNA profiling and swabbing was abandoned and officers tried to catch him in the act.

A huge manhunt was launched to catch the burgling gerontophile, also dubbed the Minstead Man, who had been targeting elderly victims across south London for almost two decades.

Dozens of officers were used to watch the areas where Mr Grant had allegedly been operating.

Grant would lie in wait outside of a property, usually in the rear garden.

From the darkness he would watch elderly residents go from room to room, switching off lights, ascertaining whether they lived alone or not.

Using a trick he had learnt about early double glazing weaknesses he would peel off the beading that held the window frames in place and lift out the entire window.

Once inside he would often cut the phone lines and pull out fuses so the houses were plunged into darkness.

Once he had achieved this he would remove light bulbs and creep, balaclava-clad, upstairs into his victims' rooms and shine a torch in their faces.

In his earlier offences he would spend several hours in each property, moving from room to room or sitting with his victims.

His oldest rape victim was 89 and his youngest 68.

He is suspected of more than 200 offences of rape, burglary and sexual assault over almost two decades of remaining undetected.

In 1999, after the review of Operation Minstead, Grant was observed leaving the scene of a burglary and his number plate recorded.

When detectives looked into this witness report they mistakenly took him for another Delroy Grant that had already been pulled in and his DNA taken.

They believed Grant to be the same man which led to him committing a further 146 offences, 20 of which were sexual assaults, two rapes and one digital rape.

He was finally caught in November 2009 after popping up again in Shirley.

Several burglaries, bearing all the hallmarks of the Night Stalker, sparked the police into launching a 70-man observation operation.

Specialist covert observers lay in wait in streets across Shirley waiting for Grant to surface.

They were aware, from previous footage of him operating, that he was driving an old style Vauxhall Zafira.

Specialists were brought in to work out the age, model and make of the car, which fitted with Delroy Grants vehicle.