The National Investigation Agency (NIA) continues to search the premises of controversial Islamic preacher Zakir Naik, his NGO and a few associates for the third consecutive day, even as it blocked the website of outlawed Islamic Research Foundation founded by him.


The anti-terror investigation agency is also set to summon Naik, who is abroad ever since his name cropped up after the Dhaka terror attack on July 1 when one of the terrorists involved posted on social media that they had been inspired by the former's speeches.


Search operations were carried out by the NIA at the offices of IRF, premises of Naik as well as that of Harmony Media Pvt Ltd, from where the programmes were being aired on Naik's Peace TV.


The agency also blocked the website of IRF, which was allegedly promoting "hate speeches" of Naik.


"As part of the investigation, all actions that need to be taken against a proscribed organisation, including the banning of its online activities, are being undertaken," said an NIA spokesperson.


Last week, the central government banned the IRF and declared it as a terrorist organisation under the Unlawful Activities Prevention Act for five years.


If the Islamic preacher fails to respond to the NIA summon, a red corner notice will be issued against Naik through Interpol by it.


The NIA is still trying to block Naik's Facebook page, Twitter account and YouTube videos that contain alleged "objectionable" material and may seek help from authorities in the US where the servers of Internet giants like Google and Yahoo are located, officials confirmed.


The agency is expected to examine cases relating to 50 individuals who were allegedly drawn to extremism after listening to Naik's sermons.


Naik has been booked along with unnamed IRF officials under section 153-A of IPC (promoting enmity between different groups on the grounds of religion and doing acts prejudicial to maintenance of harmony) besides various sections of Unlawful Activities (Prevention) Act (UAPA).