CSI 7/7; In 60C heat, forensic police piece together the London bombs atrocity.

Byline: JON CLEMENTS

CRAWLING through charred debris and twisted metal, a forensic officer scours the wreckage of one of the 7/7 Tube trains.

These astonishing photographs reveal the full horror of the carnage after suicide bomber Jermaine Lindsay blew himself up on the Piccadilly Line, near Russell Square, killing 26 others.

Tunnel vents were shut to stop tiny specs of evidence blowing away, sending temperatures soaring to 60C. Police faced an unprecedented forensic task after Lindsay, Mohammed Sidique Khan and Shezhad Tanweer bombed three trains. Here, we detail the painstaking search for clues:

1 MISSING BLUE POLE: Pole commuters had been holding when Lindsay blew up his bomb was ripped out of its socket and thrown some distance. The pole on the right hand side remained intact.

2 BLAST SEAT: Base and armrest shredded by the explosion from Lindsay's bomb which he detonated just out of picture at 8.50am.

3 FORENSIC EXPERT: Wearing protective suit to ensure evidence is not contaminated by his DNA, fingerprints or clothing fibres. Latex gloves are taped to sleeves of suits to be extra secure. Officers worked 20-minute shifts initially due to the heat before returning to the surface to cool down.

4 PHOTOGRAPHER: Officer records events on video to show jury in any trial. Detectives examined the footage repeatedly trying to learn more about the attacks for training and analysis.

5 COLLEAGUE CHECKS SEATS: Officers also wore masks over fears there could be toxic fumes left by the hydrogen peroxide explosives or even asbestos in carriage. Police helmet is to protect against falling debris.

6 YELLOW WIRES: Leads to supply electricity to the overhead lighting installed by engineers because carriage was pitch black in tunnel.

7 WHITE WIRES: Power cables for train lights that had fallen through ceiling. They were no longer live but they still hampered movement around the carriage.

8 PLASTIC EVIDENCE BAGS: For officers to put fragments of clothing, possessions, suspected bomb debris and other items for later analysis.

9 METAL PANEL AT END OF SEATS: This has buckled inwards due to force of blast.

10 WHITE STRIPS: Bits of paper with individual reference numbers were attached to parts of the carriage where bodies or body parts were found. Many relatives of victims still do not know where their loved-ones died due to the lack of any inquests.

11 CARRIAGE FLOOR: Blast has ripped floor away exposing beams train is built on. Red wires poking up carried power for brakes.

FORENSIC officers on platform at Russell Square Underground station log evidence bags their colleagues have recovered from inside the blown up Tube carriages. Each one is given its own unique number to preserve its continuity and prove where it was found. Some are clearly marked "potential health hazard".

THE search for clues stretched far outside the carriage Lindsay blew up with officers checking the tracks for any fragments which could have been blown down the tunnels. The Piccadilly line stayed closed for nearly a month, partly to give police time to scour every inch of rail. This officer works by torchlight to lift ballast with a scraping tool.

POLICE used a pounds 6.90 B& Q garden sieve to sift through piles of glass, metal and ash searching for parts of the bombs to help identify the terrorists. A magnet attached to the sieve separates metal fragments from the others. To save time, much of this work was carried out under temporary lighting inside the tunnel where the bomb went off.

TWO forensics officers make a preliminary examination of collected ash and burned debris laid out on a makeshift table. The surface is covered in a plastic sheet to improve visibility. The experts, in masks and white forensic suits, used sterile plastic tweezers to painstakingly pick out any potentially significant pieces for closer inspection.

CAPTION(S):

BOMBER Evil Lindsay