Kathmandu: Asia's infamous serial killer Charles Sobhraj, who is serving a life term in a Kathmandu jail, has filed an appeal with Nepal's Appellate Court against his sentence in the 28-year-old murder case.

Sobhraj, a French national, was sentenced to life by a Nepalese court in August after holding him guilty of murdering American woman Konizo Brohich in Kathmandu in December 1975.

The 60-year-old notorious criminal has filed an appeal against the sentence given to him by a lower court on the ground that there was no sufficient evidence to convict him in the murder case.

Sobhraj, known as "the serpent" for his talent for disguise and escape, was arrested from a Kathmandu casino in August last year.

He had also spent 20 years in jail in India for drugging and robbing tourists before he was deported to France in 1997.

The appeal filed by Sobhraj's lawyer was registered last Friday.

Meanwhile, the Home Ministry has ordered a probe into reports that Sobhraj was being allowed to use a mobile phone inside the jail.

Sobhraj has been using a laptop computer inside the prison with the permission of the jail authorities. However, he has not been permitted to use mobile phones inside the prison, 'The Kathmandu Post' reported quoting police sources.