An eyewitness, Silvia Hajas, 47, a homemaker, was playing on a nearby sand dune with her eight-year-old daughter when she heard the boys' cries for help.

An eyewitness said that she saw about seven boys 50 meters away from shore.

The body of a secondary school student reported missing in the waters off East Coast Park, on Monday (May 8), has been found.

The Singapore Civil Defence Force (SCDF) posted the update on its Facebook page at around 3.30pm.

A police spokesman said the body of the 12-year-old boy was found by SCDF officers and pronounced dead at the scene. Police are investigating the unnatural death.

The SCDF was alerted to the incident at 12.25pm. When The New Paper arrived at the scene at around 1.50pm, the area near Xtreme Skate Park was cordoned off.

About six lower secondary school boys wearing Jurongville Secondary School's uniform were seen in the cordoned off area.

An eyewitness, Silvia Hajas, 47, a homemaker, was playing on a nearby sand dune with her eight-year-old daughter when she heard the boys' cries for help.

She told TNP: "There were about seven boys 50 meters away from shore. Three managed to swim back while four seemed to have more trouble staying afloat."

She said she rushed into the water and pulled two boys out. A third boy was rescued with the help of another man using a lifebuoy.

The fourth boy disappeared by the time they had rescued the third boy, Ms Hajas told TNP.

She added the missing boy was not wearing a T-shirt.

"That sea is very harsh and deep. My feet couldn't touch the ground," she said.