Lismore CBD residents and shoppers will be seeing unusual sights and hearing unusual sounds from mid-afternoon Wednesday as members of the Australian Defence Force (ADF) arrive and conduct military exercises at the airport and the old Trinity Catholic College site.

You need to be aware that you will see 'enemy role players' operating in the CBD. These people will be unfamiliar faces, be dressed in civilian clothes and may look relatively suspect, but there is no cause for alarm.

On Thursday, September 7, the military exercise will include a 'blank fire clearance' of the old Trinity College, so residents will hear a number of blank shots fired from 1pm and then again on Friday (September 8) morning, when the exercise is repeated, from 9:30am until about 12 midday.

As Trinity is still the main bus exchange on Brewster Street, parents are informed the exercise will be completed by the end of the school day.

ADF members will also conduct a riot control activity at the Lismore Airport on Thursday, 7 September as well.

Saturday morning is a pack-up and ready-to-leave day.

A defence spokesperson said, "The exercise is designed to prepare members from the 7th Brigade to deploy on Australian Government tasks."

The Lismore App understands that this group of soldiers is preparing for short-notice government tasks for the next two years. The group can be quickly deployed at very short notice.