The body of a man who went missing off Sisters' Island has been recovered after three days.

The 41-year-old visited the island with his wife, and had went snorkelling on his own on Dec. 6.

Police told Mothership they were alerted to a call for assistance at the sea off Sisters' Island at around 12:40pm that day.

The body of the man was subsequently found and retrieved from the waters on Dec. 8 at about 5.45pm.

This was after a search and rescue operation was conducted by the Police, the Singapore Civil Defence Force and the Maritime Port Authority, The Straits Times reported.

Police are currently investigating the unnatural death.

Various people helped with the search

On Sunday, a 25-year-old park visitor who wanted to be known as Ariff told ST that the man's wife had approached him looking panicked, and asked if he had seen her husband.

The woman said that her husband had been missing for four hours.

This was after he informed her that he intended to snorkel by himself for 30 minutes.

Ariff said that he was "shocked" at how the man had been missing for so long, and proceeded to enter the water where the man was supposedly last seen snorkelling.

However, he said the water was very deep and the currents very strong.

According to The New Paper, a Facebook user by the name of Aero Max also described his experience searching for the missing man.

Max said he was asked for a last-minute charter job at 9pm by the man's distressed family member.

Although the island was pitch dark by then, the man decided to help the family out by contributing to the search with a dive boat.

Some risks involved

Sisters' Island is located to the south of Singapore. Snorkelling and diving there is a popular activity.

However, according to nature site WildSingapore, the currents around the island are very strong, and swimming outside of the lagoons is not advisable.

Diving operators TNP spoke to added that the waters there are quite strong and unpredictable, and that although snorkelling is a relatively safe activity, it should ideally be done in pairs, as with any other water activities.

Top photo from NParks