The Netwalker ransomware group has hit the sole electricity provider for the city of Karachi, K-Electric, with a ransomware attack and is demanding a $7.7 million bitcoin ransom.

According to BleepingComputer, K-Electric is Pakistan’s largest power supplier and serves 2.5 million customers. It employs 10,000 people and since yesterday, customers have been unable to access their account’s online services because of the attack.

Per the report, K-Electric was sent a Tor payment page, in which the ransomware operators demand $3.85 million in bitcoin as a ransom to unencrypt the firm’s data and stop disrupting its services. If the ransom isn’t paid within seven days, the amount will increase to $7.7 million.

The page reads:

If there is no payment made by September 15, the price increases by x2 and will be $7.7 million (765.6358 BTC).

The payment page also includes information on data the Newalker ransomware group reportedly managed to steal from K-Electric before encrypting its files. It did not reveal how much data was stolen, but the threat is likely that private documents will be released if the firm does not pay. In some cases, the attackers sell customer information on the dark web.

Netwalker has reportedly been active since last year, infecting various victims. Its threat improved in March of this year, when it started recruiting skilled hackers and focusing on enterprise networks, Bleeping Computer writes.

A McAfee report details that the change in tactics has seen the ransomware gang earn over 2,795 BTC ($28.7 million) through attacks on its victims. The funds are believed to be store in cold wallet addresses the gang has.

Netwalker was reportedly behind recent attacks on Argentina’s immigration offices, U.S. government agencies, and the University of California San Francisco (UCSF), which paid the hackers a $1.14 million ransom.

Featured image via Pixabay.