The Andrew Road triple murder was a case of robbery turned murder in a bungalow at Andrew Road, Singapore, in 1983. The robbery was committed by two young men, Sek Kim Wah and Nyu Kok Meng, armed with a rifle and knife. During the robbery, Sek murdered three of the five hostages while the Nyu protected the remaining two hostages from his partner. Eventually both were arrested, with Sek charged with murder and hanged while Nyu, who did not take part in the killings, receiving a life sentence and caning for armed robbery. It was further revealed in police investigations that Sek was also responsible for an unrelated double murder of two more victims, whom he killed using the same modus operandi as for the Andrew Road victims. He is seen as the first and only serial killer in Singapore to date, albeit Adrian Lim killed three victims in three separate instances.

On the morning of 23 July 1983, at around 8 am, 10-year-old Dawn Jacinta Tay Aishan (Chinese: 郑爱姗), the youngest daughter of 61-year-old retired businessman Robert Tay Bak Hong (Chinese: 郑木丰), was roller-skating outside her house while waiting for her Mandarin tutor, Madam Tang So Ha (Chinese: 邓淑霞) to arrive to give her lessons. At around the same time, two houses away, two young men were fixing their motorcycle. The tutor arrived at the house thirty minutes later.

Forty minutes after the arrival of Dawn's tutor, the two men seen repairing the motorcycle - 19-year-olds National Serviceman Sek Kim Wah and Malaysian Nyu Kok Meng - saw the front gate of Dawn's bungalow left open. They took out a loaded M16 rifle (which Sek had stolen from Nee Soon military camp where he served his National Service) and brandished a knife before barging into the bungalow, first taking the Tay family's Filipino domestic helper Jovita Sandrina Virador (nicknamed Duby, also spelled Jovita Merador, Jovita Verador, Jovita Verazor or Jovita Mirador), aged 27, hostage. They entered the house with Jovita and used the rifle to threaten Dawn, Tang, and Dawn's 40 or 45-year-old mother Annie Low Au Ie (Chinese: 刘爱仪), forcing them inside a room before tying them up. One of the men forced Dawn to call her father, who was in the back garden; Robert Tay was lured into the room and tied up as well.

After telling Sek where to find her jewelry, Low was told to write a cheque for $5000^{[citation needed]}, which was immediately taken by Sek to the bank to cash while Nyu stayed behind to guard the hostages. Feeling sorry for the tutor, whose head was covered in a plastic bag, he removed it for her. Sek returned with the money but was not satisfied with the loot they had, so he took Tay to the bank with him to withdraw more cash. During the time Sek was out with Tay, Nyu told the women that he would not harm them, as it was his first robbery and he had no intention to harm anyone. At the request of Low, Nyu shook hands with Dawn as a promise to not hurt them.

Sek later returned with $7,000. After gagging the victims and taking Tay, Low, and Jovita into separate rooms, the robbers continued to ransack the house. Afraid of leaving behind witnesses, Sek secretly decided to murder all the hostages. He first used a raffia string to strangle Tay, before using a wooden stool to repeatedly bludgeon him until he was dead, fracturing his skull. He entered the master bedroom, where he strangled Jovita and Low, again using a wooden stool to repeatedly strike Low's covered head.

After being alerted by the thumping sounds in the house and witnessing Sek's actions, Nyu armed himself with the rifle and locked himself in the room with Dawn and her tutor, intending to protect the surviving hostages. Sek later returned to the room where Nyu, Dawn, and Tang were hiding and demanded that Nyu let him in to murder the remaining hostages, actually intending to also kill Nyu. Nyu adamantly refused and asked Sek why would he commit murder when he had already robbed the victims of their money, and told Sek to leave. After a heated row between the two men, Sek left the house in Tay's Mercedes car with the loot.

Nyu then released both Dawn and Tang and told them to run away, informing them of the murder of Dawn's parents and maid and furnishing them with Sek's address. He drew a map of the area where Sek lived in on an envelope and gave it to Tang, who was afraid that Nyu still might harm her and her student and secretly armed herself with a small knife. Nyu also gave her his Malaysian identity card, telling her to help him buy a coffin and inform his parents and grandmother that he was sorry, as he wanted to commit suicide. He also asked Tang to bury him next to his deceased best friend Lau Beng Hiong (Chinese: 刘明雄), whose Chinese name he wrote inside Dawn's exercise book before giving it to her.

Nyu wanted her to repeat his requests, and despite her fear of Nyu, Tang tried to dissuade Nyu from committing suicide. It was only when Nyu pointed the rifle at her that Tang fled the house with Dawn (who saw her parents' bodies) to a neighbour's house to contact the police. Nyu tried to shoot himself twice, but failed, as he did not know how to use the rifle. Frustrated, Nyu fled the bungalow, but not before leaving behind the rifle and stolen ammunition, for fear that Sek would murder more people. He met up with Sek in another safe place that afternoon to divide the loot. Nyu later left Singapore on that night itself for Malaysia using a friend's passport, while Sek remained in Singapore.