Firefighting efforts put smoke over Hobart

Back burning efforts for a blaze northeast of Hobart are sending smoke over the city but crews are confident of having contained the fire.

Burning for more than six days through inaccessible bush including state forest, conservation area and private land, the fire near Runnymede has covered some 2600 hectares.

"Back burning that has been occurring over the last few days has significantly increased the size of the fire, and with that comes a significant increase in smoke," Tasmania Fire Service controller Stuart Males said.

Crews have battled strong winds over the weekend as they worked to control the fire, which is still expected to require monitoring for several days.

Investigations continue into the cause of the fire.