As PC Kulwant Sidhu, 24, lay on the floor in the workshop in Colne Road, blood pumping from his right arm, he managed to press the transmission button on his radio for four seconds but was unable to speak.

PC Sidhu, a promising young officer already marked-out for promotion, climbed onto the roof of the workshop shortly before midnight on October 25 last year having watched burglars scramble onto the building after emerging from an nearby studio.

From the rooftop he provided a radio commentary for officers on the ground as they tried to talk the two men down from the roof.

Minutes after his third radio report there was a loud crash, the court was told last Thursday.

Sergeant Alison Dollery broke down as she described to the jury how she heard the crash and thought it had come from the courtyard next to the workshop.

She said: "I believed there was a third suspect. We had information that there was someone running round."

The jury heard how officers realised PC Sidhu was missing when they had arrested Elsworthy and Maiden.

Attempts were made to contact him on his radio at 12.04am, to no avail.

Shouting

Sgt Dollery said: "It was at that time that I knew something was wrong. I heard officers shouting his name.

"I decided to put PC Tyrell on to the roof of the workshop. He shouted that there was a hole in the roof."

At 12.13am PC Sidhu managed to press his transmission button but it was not until 12.27am that the emergency services were called.

Firefighters from Twickenham arrived to find police officers desperately trying to force open the workshop door.

PC Sidhu's brother and sister walked out of court when Ricky Elsworthy and Andrew Maiden, both subsequently convicted of burglary by Richmond magistrates, appeared to give evidence.

They told the jury that they had not seen PC Sidhu on the roof of the workshop or heard the crash.

But Mr Maiden said: "The roof was slippery. I remember slipping all over it as I came across it."

PC Sidhu, who lived with his parents in Hayes, was pronounced dead at the scene at 1.20am.

Dr Richard Shepherd, who performed the post mortem at Kingston Hospital, said PC Sidhu had severed the major blood vessels and muscles in his right arm after falling through the skylight.

He said the wound was probably caused by a large piece of glass and told the court that without treatment it was likely that PC Sidhu would have survived for 10 to 15 minutes.

Coroner Alison Thompson expressed her deepest sympathy to PC Sidhu's family as she recorded a verdict of accidental death.

She said: "PC Sidhu was a great asset to the police force. He was dedicated to his work and was an enthusiastic, humorous and dedicated officer.

Enthusiasm

"The way in which he died showed the enthusiasm he had for the work he did."

Outside the court Commander Alan Shave paid tribute to PC Sidhu, who joined the Metropolitan Police in 1995 and was tipped to join Richmond's crime squad.

He said: "Kulwant Sidhu was an exemplary police officer who had a promising career ahead of him.

"He will be greatly missed by all his friends in the Metropolitan Police."