A PERSONAL trainer has been charged over a “ferocious” stabbing attack on a teenager at a supermarket in Sydney’s up-market inner-west.

Witnesses said there was “blood all over the floor” after a 16-year-old was stabbed in the hand and abdomen in the car park of a Woolworths in Balmain on Thursday.

Yesterday, police arrested 29-year-old personal trainer Jeremy Allen who they allege asked a 16-year-old victim for a lighter before stabbing him.

After a dramatic raid, Allen was charged with cause wounding or grievous bodily harm with intent to murder, reckless grievous bodily harm and reckless wounding.

However, his solicitor, Ronnie Naidoo, told his Parramatta Bail Court yesterday that his client — who appeared sporting a bandaged left hand — had a “very strong argument for self-defence”.

Allen’s weightlifter girlfriend, Cassandra Ross, 23, was also arrested at home yesterday and has been charged with concealing a serious indictable offence. She will face Central Local Court on Wednesday.

Despite the self-defence claim, prosecutor Amber Hawkins claimed Allen fled the scene of the crime, changed his appearance, didn’t hand himself in, had previous violence-related offences and had breached AVOs in the past.

He was refused bail by Magistrate John Favretto and will remain behind bars until September 11 when he is due to face Central Local Court.

Acting Superintendent Anthony Bell told reporters on Friday the 16-year-old victim — who underwent surgery at Royal Prince Alfred Hospital and remains in a stable condition — was with his brother and another friend at the time of the attack.

He said police would allege he was simply “grabbing groceries” when he was approached by male.

“This was a teenager who was just attending a local supermarket with his friends,” he said. “He was confronted by a male in car park; there was a short one way conversation whereby the victim was asked for a lighter after which followed a swift and unprovoked attack, with a stabbing to the hand and abdomen.”

He said the boy’s hand injuries may have been caused by him defending himself from the repeated blows. The teen is not previously known to police.

“All parties have been traumatised by this incident,” he said.

The victim’s mother said that she couldn’t understand why her son had been targeted.

“I don’t understand it at all. I don’t know how anyone can hurt a child, let alone someone they don’t know,” she told Nine News.

“My other son did an amazing job, he’s a very switched-on kid, and he held it together through that period. In calling the ambulance first (he) probably saved his life.”

— with wires