The pensioner was digging for scrap metal when she hacked into a fibre-optic cable which runs through Georgia to Armenia, forcing many thousands of internet users in both countries offline for several hours on 28 March.
"She found the cable while collecting scrap metal and cut it with a view to stealing it," Georgian interior ministry spokesman Zura Gvenetadze said.
The woman who was arrested in the village of Ksani, north of capital Tbilisi, has been charged with damaging property and could face up to three years in prison if convicted.
"Taking into account her advancing years, she has been released pending the end of the investigation and subsequent trial," Gvenetadze said.
Many Georgians' internet connections were also briefly cut in 2009 by another scavenger who damaged the fibre-optic cable while hunting for scrap metal in the impoverished ex-Soviet state.
The company that owns the cable, Georgian Railway Telecom, said that the latest damage was serious, causing 90 per cent of private and corporate internet users in Armenia to lose access for nearly 12 hours while also hitting Georgian internet service providers.
"I cannot understand how this lady managed to find and damage the cable," the head of the company's marketing department, Giorgi Ionatamishvili, said.
"It has robust protection and such incidents are extremely rare," he said.
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