New Delhi - Indian investigators are probing whether David Coleman Headley a US citizen of Pakistani origin now detained in the United States, had any links to the November 2008 attacks in the city of Mumbai, news reports said Friday.

Headley and his alleged accomplice, Tahawwur Hussain Rana, a Canadian citizen of Pakistani origin, were arrested by the US Federal Bureau of Investigation (FBI) in October on charges of plotting terrorist acts.

The two men are suspected of planning attacks in India, where targets included a school for military officers, and a Danish newspaper that published cartoons denigrating the Muslim prophet Mohammed in 2005.

According to information shared by the FBI with Indian intelligence agencies, Headley's passport revealed he ran a visa agency in Mumbai for almost two years until July 2008 and had travelled to India on business visas nine times between 2006 and 2009, the IANS news agency reported, citing intelligence sources.

Headley's last visit to India was in March 2009. He is believed to have gathered extensive details on the National Defence College in New Delhi, one of the alleged targets of a terror plot, on his three-day trip.

Headley's passport shows he visited Mumbai, Kochi in the southern state of Kerala, Ahmedabad in Gujarat, western India as well as Lucknow and Agra, two cities in Uttar Pradesh during previous trips.

Investigators suspect that these trips could have been for reconnaissance purposes.

"It is strongly believed that Headley may be the missing link in the 26/11 attacks probe. We are keenly looking at it," IANS quoted an intelligence official as saying on condition of anonymity.

More than 160 people were killed in the gun-and-bomb attacks carried out in Mumbai between November 26 and 29, 2008, by 10 gunmen, who, according to Indian investigators reached the city by sea from Pakistan.

India has blamed the Pakistan-based Islamic militant organization the Lashkar-e-Taiba for plotting the attack.

Headley allegedly joined the Lashkar-e-Taiba in 2006.

India's National Investigating Agency had filed a case against Headley and Rana for allegedly plotting terror attacks against India, federal Home Minister P Chidambaram said Thursday. (dpa)