Residents reported that the tremors and noises occurred about 9pm on Tuesday.

People felt the disturbance in East Maitland, Lorn, Horseshoe Bend, Oakhampton and Bolwarra.

“My house shook in Melbourne Street, East Maitland, and it was loud, [I’m] extremely scared, does anyone know what it was?” Suzy Folpp wrote on the Mercury’s Facebook page.

“A single, deep, very loud boom,” Francis Young wrote.

“A neighbour and I stood outside for a few minutes to listen for any follow-up sounds for a clue, but heard nothing other than a coal train rolling in the distance.”

Australian Defence Force ­personnel are completing training activities in the Hunter Valley, Newcastle and Port Stephens regions until tomorrow.

A spokesman would not ­comment on whether Tuesday’s disturbance was related to the training exercises, but confirmed that aircraft training had taken place in Hunter skies before 11pm.

Aerial training involved F/A-18A Hornets, PC-9 aircraft and Black Hawk aircraft.

“Residents may notice an increase in military movement and noise during this time, but should not be alarmed as this is part of the activity,” he said.

“The training is conducted to ensure that Defence has the highest level of capability to support Australia and its national interests.

“Training in densely populated areas is essential to provide ADF personnel with realistic training environments.

“Defence acknowledges that these activities may result in ­disturbances to residents, but wherever possible we seek to ­minimise the disruption.”