The authorities received 31 cases of neighbourly disputes involving parties with suspected mental health conditions in the past three years, an issue that has come under the spotlight due to the actions of an elderly Toa Payoh resident.

Health Minister Gan Kim Yong, in a written parliamentary reply yesterday, said these cases were received by the Agency for Integrated Care between 2015 and last year.

Eight of them were referred to the Institute of Mental Health (IMH) for treatment due to active mental health symptoms, said Mr Gan, adding that the IMH does not maintain data on the number of such cases which are referred by the police or other agencies.

He was replying to a question from Non-Constituency MP Daniel Goh on the number of cases referred to the IMH by the police or other agencies arising from neighbourly disputes.

In a statement that was issued late on Sunday night, the Bishan-Toa Payoh Town Council said that an elderly Toa Payoh resident whose "irregular behaviour" has sparked fear among neighbours does not pose any danger to herself or others.

Town council chairman Chong Kee Hiong, an MP for Bishan-Toa Payoh GRC, said that the agencies are aware of the antics of the woman, who lives in Block 55, Lorong 5 Toa Payoh.

Agencies such as the Housing Board, residents' committees, voluntary welfare organisation Care Corner and the neighbourhood police centre have been working in recent months to help her.

The Straits Times first reported last Saturday that residents in the block were concerned about their safety after the woman was seen flinging burning items over the parapet.

She also splashed what appeared to be a corrosive liquid outside her home, which caused the paint on the walls to peel, exposing bare bricks at certain spots.

For the past two months, the woman shouted loudly every morning, said neighbours.

Mr Chong said in his statement that the woman lives in a rental flat with her husband.

The couple are in their 70s.

During a visit to the flat, grassroots leaders found that the woman had used salt, vinegar and baking powder to scrub the wall and floor to supposedly "get rid of spirits", he said.

She would also throw cold ash over the parapet.

Mr Chong said the agencies' most important goal in their concerted efforts would be to get professional help for the woman.

However, despite repeated attempts by the agencies, she "adamantly refused offers of help", he added.

"The police are monitoring if there are adequate grounds to compel her to seek professional help, but their current assessment is that she poses no danger to herself or residents," said Mr Chong.

Repair works had been carried out to fix the damage along the corridor, but despite being issued warnings, the woman has persisted in her actions.

The agencies noted that the couple have lived in the block for around 10 years and that relocation would not solve the problem. "It would be unfair... to simply transfer the problem to another precinct and this may exacerbate the wife's condition," Mr Chong noted.

Nevertheless, alternative housing arrangements will be made if her condition does not improve despite treatment.

In the statement, the agencies reiterated that they would take the safety of all residents into account in dealing with the issue, and expressed hope that a satisfactory outcome will be reached.

One reason for the difficulty in tackling such problems is that psychiatrists and law enforcement officers may differ in their view of whether a patient's actions are of harm to himself or others, said psychiatrist Lim Boon Leng.

"If someone is at a substantially high risk of harming others or attempting suicide, we can recommend for him to be admitted involuntarily," said Dr Lim.

But law enforcement officers, who are responsible for transporting patients to the IMH, "may not interpret it the same way" if no crime is committed.