A teenager has been found guilty of murdering Polish nursing assistant Magda Pniewska who was shot in the head as she walked home from work.

Armel Gnango, 17, had denied killing Magda, 26, who was taking a short-cut through a car park and talking to her sister in Poland on her mobile phone when she was caught in cross-fire between two youths.

Gnango was also found guilty of attempted murder of the second gunman and having a gun with intent to endanger life. He pleaded guilty to having a prohibited weapon.

The court was told it was not his gun which fired the fatal bullet in John Williams Close, New Cross, south London, last October.

But prosecutor Brian Altman QC said Gnango was still responsible for the killing because he was involved in the gunfight.

The court was told a second youth, who had a red bandana over the lower part of his face, was also arrested but not charged.

He was named by Gnango but denied being involved. Police had insufficient evidence to charge him, the court was told.

Mr Altman said: "In scenes reminiscent of the Wild West, Magda was to become the innocent victim of a gunfight by two total strangers.

"She was caught in the cross-fire between two youths armed with handguns. Each had a score to settle.

"The gunfight tragically ended the life of a young woman who had fearlessly given her life to caring for others."

Gnango told the court he was talking to a friend in a car when he saw the other youth on the stairs taking a gun out and firing.

He said he assembled a gun which he was going to sell for a friend, as he sheltered behind the car.

"I put my hands over my head as I was crouching and let off a shot - it was not more than two shots," he said.

"I was aiming at the sky. I had never shot a gun before. I was panicking. I was trying to scare him off."

But Mr Altman said the youths had fired their weapons oblivious of who was around. Gnango's version of events was not accepted.

It was probably Gnango running off towards an alley that had made the other gunman change the direction he was shooting, hitting Miss Pniewska by mistake.

The two gunmen had been unharmed. The 9mm pistols were found months later - the defendant's in a bag near a sports centre and the other gun in a scooter during a police search.

Gnango was remanded in custody until June 23 when he will be given a life term with a minimum number of years he will serve.

An impact statement from Miss Pniewska's mother Barbara was read in court.

It said: "We have lost a much-loved and loving daughter. My child's life has been untimely cut short.

"The ray of sunshine which was Magda, has gone from our family."

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