Published: 16:00, 12 November 2014
Screams from a young woman were heard by several people at the time teenager Claire Tiltman was killed, a court heard.
One was ill in her bedroom backing on to the alleyway where the 16-year-old was fatally stabbed and another was sitting in a nearby doctor's surgery waiting room.
But a jury at Inner London Crown Court where former milkman Colin Ash-Smith, from Swanscombe, has denied murder, was told they thought it was children "mucking around".
Claire died after being knifed nine times in an alleyway off London Road, Greenhithe, just before 6.30pm on January 18, 1993.
It is alleged Ash-Smith, described as a knife-obsessed loner, killed the teenager "for the sake of killing".
On day five of the trial in South East London, the court heard that Denise Spicer was ill in bed at her home in Ivy Bower Close.
She was watching an episode of the hit US TV series Roseanne when, between 6pm and 6.15pm, she heard two loud screams.
In her statement to police, which was read out in court, the building society cashier said: "I can only describe them as shocking screams that came from a female and from the direction of the alleyway at the rear of my house."
She added there was a short gap of a second or two before she heard more screams.
"The second screams were not as loud. I felt it was kids mucking around and this, together with the fact I was feeling unwell, caused me to stay in bed."
Kelly Wales was waiting to see her GP at Ivy Bower Surgery when she heard two "faint" screams.
"They came very shortly after each other," her statement read. "They sounded as if they came from just outside the surgery."
She added that there was a pause of about two seconds between the screams but no one else in the surgery appeared to hear.
"I thought it was a child playing up," Ms Wales told police at the time.
The court heard her appointment with her doctor was then interrupted by the receptionist coming in to say there was a young girl in the alleyway and "a lot of blood".
Motorist Mark Ingram was driving up London Road when he heard two "fairly short screams" from a girl.
He believed they had come from the church on his right-hand side and decided not to stop because he thought they were made by children messing about.
He told police in a statement that when he discovered the next day what had happened, he realised "to his horror" what he had heard.
Referring to the fact he had not stopped, Mr Ingram added: "It is to my deep regret and something that will always live with me."
The trial continues.
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