New Delhi: In a rare case, doctors removed a dead foetus from a 15-year-old Malaysian boy's stomach. The foetus of the boy's 'twin' had its own skin, hair and male genitalia when the doctors removed it.

The boy had been complaining of severe stomach ache and was also bloated since birth, but doctors couldn't place a finger on the problem.

It was only when the teenager sought urgent help at a local hospital that the bizarre source of his discomfort was stumbled upon.

The boy's unborn twin, which the doctors mistook for a tumour, was draining his blood supply and feeding off him.

According to a report in the Daily Mail, surgeons at Sultan Abdul Halim Hospital in Sungai Petani found the foetus, which weighed 3.5lbs (1.6kg) and had deformed limbs.

The non-viable baby, meaning it wasn't capable of living independently, had no mouth, umbilical cord or placenta, they wrote in BMJ Case Reports.

They initially requested CT scans for the boy when they felt a tender, hard mass over the central part of his abdomen – a tell-tale sign of a tumour.

Scans then revealed a 'huge intra-abdominal mass' that was 23.8cm long, which showed the development of a spine. This halted their suspicions of cancer.

They wrote: 'Components in favour of a foetus that were seen within the mass include deformed skull, vertebral body and long bones,' the Daily Mail said.

Post the complex operation, doctors handed over the foetus to the boy's family, as per the mother's request who wanted hold a private funeral for the unborn baby.

Foetus-in-fetu is a developmental abnormality in which a mass of tissue resembling a foetus forms inside the body.

Medical literature states that only 200 cases of the rare condition have ever been reported worldwide.