An operation is underway in  Narrabri to evacuate parts of the  CBD after a gas leak on Tuesday afternoon.

Emergency services were alerted after a 10,000 litre LPG tank started leaking shortly before 1pm.

Fire and Rescue NSW confirmed the Coles Supermarket had been evacuated and staff and students at a nearby school and TAFEcollege are also being asked to leave.

A large exclusion zone is being set up with businesses evacuated as hazmat crews try and control the leak.

Barwon St is closed to traffic and a number of diversions have been set up.

More news in tomorrow's edition of The Leader.