A Nepalese court on Monday ordered Charles Sobhraj be detained for a week to enable investigations on charges that he violated immigration laws.
Kathmandu District Chief Judge Om Prakash passed the order.
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Sobhraj, nicknamed 'The Serpent' for his talent at disguise and escapes, was arrested from a casino in Kathmandu on September 19.
The Nepal police want him for the murder of two women in 1975.
He is also accused of murdering dozens of tourists across Asia.
Legal officer Shambu Marasini said, "We are moving a case against Sobhraj under the Immigration Act and if convicted, he can be sentenced to a maximum of five years of imprisonment and Rs 50,000 fine.
"We are in the process of verifying documents to move the case."
Sobhraj has been accused of travelling on two passports, one French and the other Dutch, under two names.
He is currently in police custody at the special crime branch of the district police office at Hanumandhoka.