A homeless man grabbed a woman under a motorway bridge near Hayes before he sexually assaulted her, killed her and dumped her body in undergrowth, a court heard.
Vadims Ruskuls, 25, was believed to be sleeping rough when he allegedly pounced on Pardeep Kaur as she walked to work near the M4 in Hillingdon.
The Latvian national, of no fixed address, is on trial at the Old Bailey accused of murdering the 30-year-old hotel housekeeper on the morning of Monday, October 17 last year.
Prosecutor Crispin Aylett QC said: "This was a shocking, simply shocking crime."
Mother of one Mrs Kaur was reported missing by her husband when she did not return home from the Sheraton Skyline Hotel in Harlington, where she worked.
Her decomposed body was found nearly a week later partially buried in undergrowth near Harlington Bridge in Hayes.
Jurors heard that ground by the walkway on to the bridge was a "bleak spot" used by rough sleepers, drunks and drug addicts and was just yards from the busy motorway leading to Heathrow airport.
Mr Aylett told jurors that Mrs Kaur was last picked up on CCTV cameras at 6.33am on Monday October 17 last year as she walked past the area.
In a search of the overgrown wasteland nearby, a visiting officer from Norway, detective chief inspector Kenneth Berg, spotted a human foot sticking out from beneath a sleeping bag covered with branches which turned out to be Mrs Kaur.
A post-mortem examination failed to establish how she died but Mr Aylett said it was obvious from the way she had been found that it was murder.
Investigators who trawled through the CCTV images noticed a man under the bridge at the same time as Mrs Kaur.
Mr Aylett said that 20 minutes later, someone was picked up on CCTV dragging her body away towards the patch of ground where it was later discovered.
He said: "The prosecution allege that the man under the bridge is Vadims Ruskuls and the figure dragging her body towards the woodlands must also be Vadims Ruskuls.
"What happened in the 25 minutes between those two pieces of film? The prosecution allege that the defendant must have pounced on Pardeep Kaur at some point on the ramp, that he then sexually assaulted her and he murdered her."
The victim must have fought her attacker as the defendant was seen with scratches on his face the day afterwards, he said.
He added: "If she had cried out, her screams would have been drowned out by the sound of the early morning traffic."
Following his arrest for the murder of Mrs Kaur, Ruskuls' DNA was compared to samples taken from her body.
His DNA was matched to samples from her ankle, sock, and the left cup of her bra with a probability of "one in a billion", jurors were told.
DNA from the victim's fingernails were also found to be a match, the court heard.
The defendant, who refused to make any comment in police interviews, denies murder.
The trial continues.
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