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Black Shadow, the group of hackers who claimed responsibility for a cyberattack on the Israeli Shirbit insurance company earlier this week, on Wednesday night demanded a Bitcoin payment in exchange for not releasing more of the data at its disposal.

In an announcement on Telegram, the group wrote, “You have 24 hours to send 50 BTC to our wallet and we will not disclosure [sic] your data and also we will not sell to anybody. If you will not pay after 24 hours the price will change to 100 BTC. In third day you will have to pay 200 BTC. After that we will sell the data to others.”

The 24-hour window, the hackers said, would begin on Thursday at 9:00 a.m. 50 Bitcoin is equal to about $961,110.

The National Cyber Directorate and Capital Market Authority said on Tuesday that it was investigating the suspected attack on Shirbit and that an initial probe found that insurance details had been leaked.

The Black Shadow group claimed responsibility for attack on Twitter. Along with the announcement, the group published documents that were allegedly stolen with details of the company's customers, including personal details such as addresses, details of family members, and vehicle licenses.