Fibre optic.

Fibre optic cable like the one picture was cut. Photo: iStockphoto

Communications at one of Victoria's major bushfires have been cut after fire crews accidentally damaged a Telstra fibre-optic cable on Friday afternoon.

The loss of the cable affects 1000 landline services to Swifts Creek, Hotham Heights and Dinner Plains, all Telstra internet, and Telstra mobile services.

Other mobile providers are not affected.

The loss of internet means Telstra customers are not able to access the CFA website or app, twitter, or other web-based bushfire information.

Telstra spokesman James Howe said crews were trying to locate the damage – which was somewhere near Harrietville – and have it fixed by Saturday evening, despite some reports it could take weeks to fix.

"It was damaged by a bulldozer doing fire works," said Mr Howe. "It's dangerous and inaccessible terrain...it could take some time to find, but once they find it, they've got all the gear with them ready to make the repair."

Mr Howe said the best-case scenario for repair was "early evening" on Saturday. He said he "would be surprised" if it took weeks to fix.

He said Telstra mobile customers would still be able to call triple-zero on their phone.

A Country Fire Authority spokeswoman said that CFA communications were unaffected. A mobile communications tower had also been brought in, she said.

There had also been damage to a power cable. Comment is being sought from the electricity provider, SP Ausnet, as to the extent of blackouts.

Graham Symons, the CFA fire chief at Omeo, said internet and mobile services had been restored to the town shortly after noon. Landline coverage had not been affected, he said, as Omeo’s services were not connected with the fibre optic cable.

‘‘They’ve just come back on,’’ he said. ‘‘It went out yesterday at about 5.30pm.

‘‘People were being told it was going to take three weeks to restore and I think that’s what got people a little bit angry.’’

Sharon Wells who was holidaying in Omeo, said the fire alert system was designed around mobile coverage. 

‘‘SMS alerts were set up as fire alerts, the CFA apps give warnings and notifications, and mobile generally gives the ability to call and get calls,’’ she said.

‘‘Last night the lightning started all around us. I realized if a fire started – we are seven kilometres out of town – we couldn’t call anyone,’’ said Ms Wells, of Melbourne.

‘‘ As I drove out of Omeo through bush I had no idea of whether there were fires - we were going blind. A photographer from Bairnsdale said he saw a tree on the road smoking this morning and couldn’t call. The lightning obviously started it.’’

The 3138-hectare fire at Harrietville has been burning throughout the week and is still not contained.