A blood-soaked man who allegedly stabbed a woman with a paint scraper has been chased down a street and caught by witnesses.
The woman, 47, was arguing with a 21-year-old man in Randwick in Sydney's east on Wednesday afternoon when he allegedly stabbed her several times in the head and upper body with the paint scraper.
He then took off but was caught by two bystanders who chased him to an adjacent street, police said.
Nick Boudo was finishing work when saw two men pursuing and then detaining another man who was covered in blood.
"The first reaction was 'get off him' because we thought the guys were attacking him," he told Nine's Today program on Thursday.
"They said, 'Nah, he just stabbed someone'.
"I said 'he just stabbed what'."
Billy, one of the men chasing the alleged stabber, told Nine his first instinct was "I have to stop this guy".
The woman was taken to hospital in a serious but stable condition.
The man was also taken to hospital, under police guard, before being taken to Maroubra police station and charged.
He will face Waverley Local Court on Thursday charged with domestic violence wounding with intend to cause grievous bodily harm.
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