The number of elderly prisoners has almost doubled in the past five years, and the Singapore Prison Service (SPS) has retrofitted some prison cells with senior-friendly features like grab bars and handrails.
Last year, there were 651 inmates above 60 years old - almost double the 359 in 2012, an SPS spokesman told The Straits Times.
These elderly inmates comprised 5.3 per cent of the total prison population last year. This is almost double the 2.8 per cent in 2012.
The proportion of inmates over 60 years of age has increased each year in the past five years, said the spokesman.
Criminal lawyers interviewed attributed the rise to the ageing population in general.
"Singapore's population is ageing, and prisoners are no exception. There is no age limit to crime," said veteran criminal lawyer Edmond Pereira.
In 2015, the SPS retrofitted 25 cells within the prison institutions to cater to inmates with mobility problems. Besides the elderly, such prisoners also include those who find it hard to get around because they have lost the use of their legs, for instance.
Hence, prison cells in the Assisted Living Housing Unit are equipped with features such as handrails and grab bars.
When deemed necessary by a prison medical officer, inmates are also allowed the use of walking aids such as walking frames and crutches.
However, most of those above 60 are physically fit and able to be housed in regular prison cells, the spokesman said.
"While our prison institutions are necessarily spartan, all basic needs, including medical needs, of inmates are met," the spokesman added.
Ms Saleemah Ismail, who co-founded New Life Stories, a charity that helps incarcerated mothers and their children, noted that some prisons overseas also have facilities for elderly prisoners.
For example, some jails in Britain have equipped shower areas with safety handles and non-slip flooring. In Japan, some prisons have geriatric cells with ramps for the disabled and rubber flooring.
In countries such as Japan, the United States and Britain, the number of greying convicts has swelled in the past decade.
In Singapore, criminal lawyers interviewed said the crimes committed by senior citizens span the whole range, from sexual offences to assault and money laundering.
There are also drug offenders who have spent decades of their lives in and out of jail, said the Association of Criminal Lawyers of Singapore president Sunil Sudheesan.
Cases of elderly criminals reported by the media recently include an 82-year-old man who assaulted his neighbour and fractured her ribs and a 77-year-old grandfather who molested a teenage girl on a bus.
For lawyer Josephus Tan, his oldest client was a 75-year-old widower who befriended a Thai woman in her 40s online. The retired hawker helped the woman launder a few hundred thousand dollars in return for monetary benefit and with the hope of romance.
He was jailed for six months.
Lawyers and those who volunteer in the prisons applauded the SPS' move to make some cells senior- friendly. They noted that features such as anti-slip flooring make it safer for frail inmates, protecting them against falls.
Mr Tan said: "Even if the prisoners have done something wrong, they also have their rights. It does not mean we should not look after them in jail."