Mumbai, Mar 8 (IANS): The CBI has arrested a former Mumbai Customs officer who was impersonating as a doctor in an Uttar Pradesh medical college, 20 years after he disappeared, an official said on Friday.

Abhinav Singh was caught after he was found impersonating and working as a 'Dr Rajeev Gupta' and a Professor in a medical college in Mathura, two decades after he was declared a Proclaimed Offender by the CBI Special Court here.

Following a complaint by the Customs Department, the CBI had registered a case on September 29, 1999 against Singh and another individual as well as some private firms.

Singh was then an Appraiser at Custom House, Mumbai, and was charged with abusing his official position and wrongly confirming as 'genuine' a fake Duty Entitlement Pass Book (DEPB) submitted by the accused companies and individuals.

The alleged fraud resulted in a loss of over Rs 4 crore to the government by way of customs duty on imported goods.

For his 'services', Singh was paid Rs 500,000 and gifted a Maruti Zen car in 1998-99, said the official.

After the case was registered, Singh absconded and using fake and forged degree certificates he started working as a doctor in medical colleges and hospitals.

Finally, he was arrested while working as a 'doctor' and Associate Professor with a medical college in Mathura in Uttar Pradesh.

He was brought to Mumbai on a transit remand and produced before the Special CBI Court which has remanded him in custody till March 13.