The Research and Analysis Wing and Intelligence Bureau do not rule out the possibility of espionage in the theft of 18 computers from a high-security Defence Research and Development Organisation office in Delhi.

The computers were stolen from the offices of the Scientific Analysis Group and the Institute for System Studies and Analysis, both located in Metcalf House in north Delhi.

The Union government on Friday asked RAW, IB and Delhi Police's anti-terrorism and espionage wing to participate in the investigation.

An intelligence agency officer told rediff.com the probe is looking at the possibility of an espionage ring.

The government has ordered a review of the security of all DRDO installations in the country.

DRDO sources said 'loopholes' in the security would be plugged.

The defence ministry, in a statement issued over the weekend, claimed no 'sensitive data' was lost in the burglary.

'None of the 18 stolen computers had any live or current crypt analysis data, which are held safely elsewhere,' the statement said.

Some reports said the computers contained encryption data for the communication systems of Strategic Forces and latest war games.

The computers contained data relating to library, human resource development, continuing education programme courses, mathematical models downloaded from unclassified and open sources and papers published by scientists in open journals, the ministry said.

Some computers lost were being used to access the Internet and intranet. Two of the computers, the ministry admitted, contained 'old war games software.'

'These games,' the statement said, 'were no longer in use.'

DRDO sources said the theft seemed to be an 'insider's job.'

A senior intelligence officer agreed. "Without active support from insiders it is impossible to take out so many computers. But that is no guarantee against espionage," he said."There have been indications of ISI-backed networks targeting India's defence and strategic secrets by cultivating lower level employees at sensitive organisations," he added.