Oscar Pistorius could be refused early release from jail as a result of security concerns over his prosthetic limbs, it has been claimed.

The athlete is currently serving a five-year prison sentence for the manslaughter of girlfriend Reeva Steenkamp and it had initially been believed that he would be released on house arrest after serving ten months of his term at Pretoria's Kgosi Mampuru prison.

However, MailOnline is reporting today that prison officers have told Pistorius that he will not be eligible to take part in a tagging system as the device cannot be secured to his prosthetic limb.

"The device has to be attached physically to the offender's ankle. We cannot use it on false limbs which could be left somewhere static while the offender goes missing," said a source.

It is understood that the tag cannot be attached to a prisoner's wrist as it is too easy to remove but Pistorius has been told that, even without release on a tagging system, he may be able to apply for parole after 10 months.

The 27-year-old has been described as "quiet and calm" as he serves his sentence, after reportedly "sobbing himself to sleep" in the the days after his initial imprisonment.