Intelligence agencies had initially alerted the Terrorist Investigations Department (TID) to look for the journalist and his partner who were believed to have been staying at an apartment in Colombo.
Police intelligence sources said that the journalist had been staying at the Hilton hotel while having an apartment in Colombo.
Initial investigations have revealed that the journalist from the controversial British television channel and his partner had been travelling to Sri Lanka frequently and were possibly involved in a private business activity in the country.
The defence authorities however are trying to ascertain if the journalist was also involved in gathering information with the intention of tarnishing the image of the country.
The manager of the apartment where the couple were staying was questioned last Friday and further investigations are underway.
Channel 4 was behind the controversial video series on the final stages of the war in Sri Lanka including the ‘No Fire Zone’ video which alleges that hundreds of civilians were killed during the final battle between the army and the LTTE.
The alert on the couple was issued as government and security agencies make preparations for the Commonwealth Heads of Government Meeting (CHOGM) to be held in Sri Lanka next month.
Channel 4 had said it will attempt to be in Sri Lanka to cover the summit and will apply for access through the normal process. The government has said that if Channel 4 fulfils the requirements as stipulated by the Commonwealth Secretariat then they will be allowed into the country.