Security levels at military facilities in Sydney's south-west have been heightened amid concerns bikie gangs might attempt to break in and steal weapons.

The Daily Telegraph reports the security level at Holsworthy Army Base and the Moorebank weapons storage facility was raised on Friday, to safeguard weapons armouries from bikies.

Police sources also told the paper there are fears of possible links between the defence forces and outlaw motorcycle gangs, after last year's discovery that weapons were being sold to bikies.

A Department of Defence spokesman has confirmed security at all south west Sydney defence sites which hold weapons has been raised.

This just gets sillier and sillier every day...............terrorism wasnt enough but the "bikie menace" was.............its becoming laughable.