Around 100 long-tailed macaques were seen on the Lorong Halus Red Bridge in Punggol on Jun. 17.

In a Facebook post on Jun. 19, user Anderson Ng uploaded photos of the sighting.

Might be searching for more food

In his post, Ng added that it was his first time observing such a phenomenon.

Replying to another user's comment, he said that he spotted and photographed the monkeys at 3:11pm.

"Usually, the troop is about 20-30 (monkeys) at most, at any one location. But that day, there were really so many," he added in another reply.

Ng speculated that the monkeys could be moving away in groups in search of more food in the area.

According to the National Parks Board (NParks), being a forest fringe animal, macaques often search their immediate surroundings to explore and forage for food.

Do's and don'ts when seeing monkeys in public

NParks said in an advisory that members of the public can adopt safety measures if they encounter monkeys in public.

These include:

• remaining calm and quiet by not making any sudden movements or maintaining eye contact
• backing away slowly from the monkeys
• avoiding the area until the monkeys are gone
• using backpacks instead of plastic bags, as monkeys associate plastic bags with food
• not feeding the monkeys
• not trying to hit the monkeys
• hiding or throwing away items that may be attracting their attention

Top photos via Anderson Ng/Facebook