He was clearing leaves at the carpark in a Jurong condominium at about 7.50am when he heard someone screaming for help.
Looking up, cleaner Mr Ramri Semass, 48, saw a woman covered in blood running towards him.
"She was shouting 'Help! Help! Sir stab ma'am. Please call police'. I was shocked," he said.
The woman was Ms Jamelarin Jasmen Corpuz, 37, a Filipino domestic helper who worked for a couple living in a third-storey unit in Block 9D of Park View Mansions, on Yuan Ching Road in Jurong.
Mr Ken Ong Wei Poh, 37, had attacked his wife, Madam Koh Siang Hua, 39, with a knife after their six-year-old son had left for school.
When Ms Corpuz tried to intervene, she was badly hurt as Mr Ong turned on her with the knife.
Mr Ong is believed to have stabbed himself after critically injuring Madam Koh. The couple died later in hospital.
In a sensational twist, Mr Ong posted a long rant, which he titled "Final Note", about his seven-year marriage to Madam Koh and her family, on his Facebook account.
He also e-mailed his note, with the header "Jurong Murder", to media outlets, including The New Paper, at 8.11am.
In his note, he wrote about "suffering in silence and humilation (sic)" with Madam Koh and "what I got in return is (sic) her lies, empty promises and betrayal".
He went on to say that "knowing and loving you (Madam Koh) is really my biggest mistake in life".
His earlier Facebook posts also hinted that he may have been planning something dreadful since last November. (See report on page 4).
After she was slashed, Ms Corpuz, who was bleeding profusely, fled and ran down three storeys to the carpark, where Mr Ramri saw her.
He helped her to a nearby security guard post and called the police with his mobile phone.
Two other cleaners, sisters Juriah and Fauziah Abu Bakar, who had just turned up at work, also saw Ms Corpuz.
"I took a sarong to cover (Ms Corpuz) because she had big cuts and there was so much blood everywhere," Ms Juriah, 55, said.
"After that, I asked her where's (the couple's son). Luckily, he was at school, and her employer's mother was in Malaysia," she told The New Paper in a mix of Malay and English.
When Mr Ramri went out to the main road to seek help, he saw a Traffic Police officer on a motorbike and waved her down.
The officer radioed her colleagues for backup, he said.
RAN TO SECURITY POST
Meanwhile, Ms Fauziah ran to the main security post about 100m away to get help from security guard Lee Jee Kwang.
When Mr Lee got to Ms Corpuz, she had calmed down slightly but was still shaking uncontrollably.
He said: "She told me that her 'sir' had attacked her 'ma'am', and that she was hurt trying to protect her. As I was about to go up to check the apartment, she told me not to, because her 'sir' had a knife."
Mr Lee took a first-aid kit to try to staunch the bleeding on Ms Corpuz's wounds while waiting for paramedics to arrive.
Throughout, she kept telling the group that she was all right and that they should help her employer, Mr Lee said.
"She had a wound on her left arm that (was so deep), you could nearly see the bone. And there were wounds on her back, the back of her neck and her head," he added.
"But she still kept telling us to help her employer."
A police spokesman said they received a call for assistance at 7.56am.
When the officers arrived, Ms Corpuz directed them to her employer's third-storey unit where they found Mr Ong and Madam Koh injured.
It is understood that the couple were found in a bedroom with knife wounds.
Residents told TNP that Madam Koh had an oxygen mask over her face when Singapore Civil Defence Force paramedics wheeled her out. Mr Ong's abdomen was exposed, and a large bandage could be seen covering his stomach.
His hands were handcuffed behind him.
Mr Ong and Madam Koh were unconscious when they were taken to the National University Hospital (NUH).
They were later pronounced dead.
Ms Corpuz was also taken to NUH, where her condition is said to be stable.
A large police cordon was put up across the carpark in front of Block 9D. Crime scene investigators could be seen collecting evidence from the apartment and a parked black Jaguar XJL.
Blood stains could be seen on a kerb near the block.
The cordon was removed at about 3.45pm.
Ms Juriah, Ms Fauziah and Mr Ramri were seen cleaning the stairs with buckets of bleach and water.
It is understood that the weapon used in the attack has been found.
The police have classified the case as unnatural deaths and investigations are ongoing.
This article was first published on January 31, 2015.
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