One month into her job, a domestic worker became so incensed by her elderly employer nagging at her for taking a long time to eat that she plunged a knife into her neck, killing her.

The 38-year-old Indonesian maid, Minah, then lied to the police that Madam Tay Quee Lang, 77, had committed suicide.

Minah, who goes by only one name, was sentenced to 15 years' jail yesterday after she pleaded guilty to a charge of culpable homicide for killing Madam Tay in her Tampines Street 22 flat on Feb 13 last year.

In sentencing, Judicial Commissioner Audrey Lim agreed with prosecutors, who had sought a deterrent jail term of at least 15 years for the "senseless and unwarranted" killing that arose from a minor quarrel.

The judge said the maid's response to the nagging was "clearly disproportionate".

"It's not a case where the deceased had used any form of violence or used any threat against you," she said.

As soon as sentence was passed, two of Madam Tay's family members in the public gallery started sobbing, while another pumped his fist and uttered "yes".

After court was adjourned, the family members shouted "Satan", "Die in prison" and "Go to hell" as Minah was led away by guards.

The family declined to speak to reporters.

The High Court heard that Minah started working for Madam Tay and her husband, Mr Tan Hee Seng, 78, both retirees, in January last year.

Mr Tan employed the maid to care for Madam Tay, who needed a walking stick and assistance to move around.

By all accounts, the maid got along well with her employers, aside from one incident in which she shouted at Mr Tan when he told her not to waste water.

On Feb 13 last year, Mr Tan left the flat for a medical appointment after feeding Madam Tay her lunch and helping her back to her rattan chair in the living room.

According to Minah, Madam Tay repeatedly called out to her while she was having her lunch in the kitchen. She said Madam Tay scolded her for taking a long time to eat because she was using her mobile phone and they ended up shouting at each other.

Intending to stop Madam Tay from talking, Minah took a 22cm-long kitchen knife and walked towards her. When Madam Tay saw the knife, she carried on complaining and told the maid that she was not afraid of her, the court heard.

When Minah held the edge of the knife near Madam Tay's throat, the elderly woman tried to push the knife away. But the maid thrust the knife into Madam Tay's neck, leaving her gasping for air.

The maid then washed Madam Tay's blood off her fingernails and phoned her employer's daughter.

A neighbour, who heard a female voice crying, saw Minah pacing around the living room, murmuring "tolong tolong" or "help help". He called the police when he saw Madam Tay with a knife lodged in her neck.

An autopsy found that Madam Tay bled to death from the single stab wound, which was so deep that it reached the apex of her left lung.

Yesterday, Deputy Public Prosecutor Bhajanvir Singh argued that acts of physical violence by domestic workers against employers must be condemned.

Minah's lawyer, Mr Nasser Ismail, said his client was remorseful and would like to apologise to Madam Tay's family.