New Delhi, Feb 11 (IANS) Investigating agencies are probing if a US national detained at the Indira Gandhi International Airport late Wednesday with a knife blade in his luggage had any terror links and if his visit to India was linked to touching base with sleeper modules.

Winston Marshall, who converted to Islam over 15 years ago, was stopped by Central Industrial Security Force (CISF) personnel when he was boarding a Qatar Airways flight to Doha.

Suspicion was aroused when Marshall lied about the presence of a knife blade found in his baggage. After discovering from his passport that he had come to India after travelling to Pakistan and Bangladesh recently, security personnel took him aside for questioning.

'When he (Marshall) came to the security check-point in the hold area, an inspector found something looking suspicious in his bag through the screening machine,' said CISF's Deputy Inspector of General(DIG) Udayan Banerjee.

Marshall repeatedly denied he was carrying a knife.

The entire bag was then physically examined again and a metallic object weighing around 550 grams was found lodged in the corner of a bag. The knife was nearly five inches long.

'That he was travelling via Doha to New York, the concealment of the knife and his recent trips abroad.. all raised suspicion. We had no option but hand him over to the investigating agencies,' said a CISF official.

The case is almost reminiscent of terror suspect David Headley, arrested in Chicago in October last for allegedly plotting terror strikes in India. Headley had changed his Muslim name.

Marshall is a convert from Christianity.

'He is being questioned by multiple security agencies at the Lampur detention centre on the outskirts of the national capital,' said a senior Delhi police official.

Officials pointed out that the American embassy has been informed about Marshall's detention by the Foreigners Regional Registration Office.

Sources told IANS that Marshall came to India in October last year and had travelled to Pakistan through the Wagah border. He reportedly travelled to several cities in Pakistan and then visited Bangladesh.

'We know that he stayed in Nizamuddin when he returned in January this year. It will take a couple of days to know the real purpose of his visit to all three countries. We can't talk of his terror links as of now,' said a security official.