Rescue workers who turned up at Likok Pte Ltd in Defu Lane 4 found his left leg severed below the knee and his right foot crushed.

As he was not trapped in the machine, he was taken to Changi General Hospital immediately, even as firefighters searched for his severed leg among the pile of waste paper.

They recovered it within several minutes and rushed it to the hospital, but a hospital spokesman said doctors found it too badly mangled to be reattached.

By 8pm, he was said to be in a stable condition in the high-dependency ward.

Likok's manager, Mr Haw Say Heng, said the man was an odd-job worker whose task was to sweep the floor and collect newspapers.

He was not supposed to operate the machines, which are about 6m high.

Mr Haw added in Mandarin: 'No one saw the incident, so no one really knows what happened. We need to talk to him to find out more.'

He said that as the worker was hired through an employment agency, the company would contact the agency to get in touch with the worker's family.