An elderly woman was filmed being beaten up by a neighbour after relatives installed a security camera in a lift lobby.
Madam Toh Siew Hong, 65, was seen being approached from behind by the woman in her 40s outside their flats in Chai Chee.
Her attacker then began punching and kicking her, mostly in the face. This continued even after the victim fell to the floor.
Madam Toh - who was seen trying to hit back - received more than 50 blows during the 20-minute clash on Saturday, Lianhe Wanbao reported.
Her attacker was later arrested for allegedly kicking a policewoman and using abusive language.
The shocking footage of the fight - which has since gone viral - was recorded after the elderly victim's family installed the camera because of concerns about their neighbour's behaviour.
Madam Toh's daughter, who wanted to be known only as Ms Yap, told The Straits Times that the woman had been causing "trouble" ever since she moved in opposite their home in January.
"She would blast her music very loudly at midnight, and she stares at us, all the neighbours, in a confrontational way."
Ms Yap said her mother was under observation at Changi General Hospital, adding that she had bruises near her eyes, plus several stitches on her face and at the corner of her mouth.
Wanbao reported on Sunday that people in the block had lodged several complaints against the neighbour. It said the police had conducted more than 20 checks at her home.
"In the last few weeks, she had approached my mum several times, provoking her and using vulgar language against her," said Ms Yap.
"She probably thought my mum had complained about her to the police, but my mum didn't. So we had no choice but to install the CCTV so we could get proof." Madam Toh's family then posted the footage online.
The neighbour's son-in-law told Wanbao that she had sought treatment in the past at the Institute of Mental Health.
Police confirmed that the fight took place and said they had received a call for help at 10.17am.
A spokesman said: "It was established that a dispute between two parties had occurred."
He added that a woman in her 40s was arrested on suspicion of using abusive language and voluntarily causing hurt to a public servant. Investigations are ongoing.
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