A hushed "beep, beep" signals on the Military Intelligence (MI) handheld detector during a routine sweep in defence minister A K Antony's office last month created a sensation of someone spying on him, but the defence ministry was quick to deny any such incident.

Such sweeps are carried out everyday in all sensitive ministries. Reports say the defence ministry did not take a chance after the MI reported weak signals emanating from phones on Antony's desk on February 16 as the Intelligence Bureau (IB) was called in to analyse.

The matter was closed after the IB concluded that the stray signals cannot be due to any bugging. A TV channel, however, digging out the incident on Friday led to the defence ministry issuing a brief press note to deny any bugging.

"Reports of ‘bugging’ in South Block is wrong. Routine checks are conducted in the offices of Raksha Mantri and other officers in South Block. Nothing has been found in these checks," the press note said.

Speculations were, however, flying throughout the day on why the IB was entrusted with the probe instead of banking on the MI and whether it showed the mistrust between the defence ministry and the army since after army chief general V K Singh taking the government to court in his age dispute and why the army had to dismiss reports of its involvement in alleged surveillance on the minister. There were also reports linking the incident with a similar alleged bugging of the office of finance ninister Pranab Mukherjee last June.

The Bhartiya Janata Party claimed that spying on the defence minister is a very serious matter as it first happened with Mukherjee and now with Antony. "The forces who have to protect the country's borders are not able to protect their ministry's premises," party spokesman Prakash Javadekar said demanding a thorough probe to let the nation know whether the bugging was by some foreign force or the defence companies.

He also dismissed the defence ministry's denial on the same lines on which the bugging in finance minister's office were ruled out claiming them to be just chewing gum. No one will go on sticking chewing gum over a dozen places in the high security zone, Javadekar said, wondering if the listening devices stuck with the gum had been taken off before the probe began.

The defence ministry sources said nothing unusual should be read. The IB was called in just because its responsibility is to make the central secretariat, housing the Prime Minister's office and other important ministries, foolproof from any unauthorised entries. Also, the IB has more sophisticated devices than simple handheld detectors with which the two army personnel were scanning the premises as a routine check.

The MI staff continues with the daily scanning of the offices and that should put an end to unnecessary speculation of the defence ministry not trusting the army, the sources added.