Trashing NIA's apprehensions, the Supreme Court on Friday ordered social activist Gautam Navlakha, accused of having links to Maoists and Pakistan's spy agency ISI, to be placed under house arrest "without fail" within 24 hours.

Navlakha is under judicial custody in Taloja Jail in Navi Mumbai in connection with the Elgar Parishad-Maoist link case.

A bench of Justices KM Joseph and Hrishikesh Roy passed the order after sharp exchanges between the prosecution and the court.

The bench, however, ordered some additional security measures to be put in place at the building where Navlakha will be kept under house arrest.

"Our order of November 10 shall be given effect to without fail within 24 hours," the bench said.

The NIA had moved the SC on Thursday seeking vacation of its order for house arrest, saying Navlakha, being a charge-sheeted accused in a case involving threat to national security and integrity, does not deserve any extra leeway.

"From the investigation carried out, it is established that the petitioner delivered speeches at different forums & programmes on many issues related to the Kashmiri separatist movement and Maoist movement and supported it.

"During scrutiny of the documents seized from the petitioner it is evident that they are related to CPI (Maoist) strategic documents, documents in connection with the formation of the CPI (Maoist) party, important press releases of CPI (Maoist) party, critical secret communications with underground senior leaders of the party which establishes his deep involvement in the activities of CPI (Maoist) party," the agency said in its plea.

The bench, however, went ahead with its November 10 order of placing the 70-year-old activist under house arrest.

The top court said a kitchen door leading to the exit should be locked and sealed along with the grille windows whose keys can be kept by the NIA and another CCTV camera shall be installed at the southern door which leads to the exit.

It also allowed the NIA to monitor the CCTV camera feed from the place of their choice.

At the nearly half hour hearing, which saw some heated exchanges, the court told Additional Solicitor General SV Raju, "If you are trying to find out some loopholes to see that our order is defeated, we will take a serious view of it".

Raju, appearing for the NIA, said it is not he who is trying to find loopholes but claimed Navlakha suppressed "crucial facts" from courts.

"This man (Navlakha) has suppressed crucial facts from the court and therefore he should not be considered for house arrest," he said.

The bench wondered whether Raju and Solicitor General Tushar Mehta, also appearing for the NIA in the fresh application for recall of the court's November 10 order, meant to say with the entire might of the State and the police force they will not be able to monitor or keep an ailing 70-year-old man under house arrest.

"There are more hardened criminals than him," it said.

Mehta responded, saying: "I didn't mean to annoy the court. I am not apologetic about my perception but I am apologetic to the court. My perception is that Naxalism cannot be dealt with by the nation with a kid's glove."

The bench said the solicitor general has every right to have his perception but the judges are calm as they have been trained to remain so in such situations.

"This man had ISI links and links with separatists of Jammu and Kashmir," Mehta alleged.

Justice Joseph then asked Raju to suggest what additional conditions the agency wanted to be placed to restrain the movement of Navlakha under house arrest.

"You seal the gates and the windows, install more CCTV cameras and you would make it worse than the jail," the bench observed.

Senior advocate Nitya Ramakrishnan, appearing for Navlakha, said during the arguments that everything was disclosed to the court about her client's sister's connection with the Jaslok Hospital and it was also known to the probe agency.

Alleging that Navlakha's medical report issued by the Jaslok hospital was "vitiated", the agency had said proper treatment was given to him whenever required and his condition was manageable within the premises of Taloja central jail.

"It is submitted that it is clear from the publicly available record that Dr. S. Kothari has been associated with Jaslok Hospital since 1979 i.e. about 43 years. It is not unreasonable to assume that the said doctor, being on a very senior position in the said hospital, would wield considerable influence in the said hospital."

"It is submitted that considering the fact that a senior doctor of the said hospital is directly related to the petitioner and was a part of the (team) preparing medical report of the petitioner, that a clear case of personal bias vitiates the said report has been made out by the respondent," the NIA had said on Thursday while seeking vacation of the SC order for Navlakha's house arrest.

While contesting the November 10 order of the apex court, Mehta said, "If the question of review comes from other side (Navlakha's side) I will deal with it but there is Article 14 which says all are equal. Here is a case, which says some are more than the equal. There are other prisoners also who are older than this man and suffering from same ailments but here is a UAPA accused, who wants to be in house arrest."

The bench said it had incorporated all the conditions in its November 10 order which was suggested by the probe agency and the order was a more or less consensual.

Raju, however, added Navlakha did not disclose his brother-in-law was a senior doctor at Jaslok Hospital, where he had insisted to go, he had not disclosed that the first floor flat, where he would be staying had two exists and a library run by the Communist Party of India on the ground floor and Karate classes going on the terrace.

"When we went there to evaluate the conditions at the flat, we found a second door, which was not disclosed earlier leading to the exit, collapsible grille of the windows, through which anyone can come in or go out, library on the ground floor and people coming in and going out. This will make the policemen difficult to monitor," he said.

On November 15, the top court had cleared the hurdle for the release of Navlakha from Taloja prison by waiving the requirement of a solvency certificate for availing the benefit of house arrest.

The activist approached the apex court after the delay in placing him under house arrest.