A hooded man holds a laptop computer as cyber code is projected on him in this illustration picture taken on May 13, 2017. Photo: REUTERS/Kacper Pempel/Illustration

An anti-Iranian government hacking group with potential ties to Israel and a track record of destructive cyberattacks on Iran claimed in social media posts on Tuesday that it had destroyed data at Iran’s state-owned Bank Sepah.

The group — known as Gonjeshke Darande, or “Predatory Sparrow” — hacked the bank because they accused it of helping fund Iran’s military, according to one of the messages posted online.

The hack comes amid increasing hostilities between Israel and Iran, after Israel attacked multiple military and nuclear targets in Iran last week. Both sides have launched multiple missile attacks against each other in the days since.

Reuters could not immediately verify the attack on Bank Sepah. The bank‘s website was offline on Tuesday and its London-based subsidiary, Bank Sepah International plc, did not immediately respond to an emailed request for comment.

Customers were having problems accessing their accounts, according to Israeli media.

Gonjeshke Darande did not respond to multiple messages sent via social media.

“Disrupting the availability of this bank’s funds, or triggering a broader collapse of trust in Iranian banks, could have major impacts there,” Rob Joyce, the former top cybersecurity official at the NSA, said in a post on X.

In 2022, Gonjeshke Darande claimed responsibility for a cyberattack against an Iranian steel production facility. The sophisticated attack caused a large fire at the facility, resulting in tangible, offline damage. Such attacks are usually beyond the capabilities of activist hackers, security experts say, and would be more in line with the capabilities of a nation state.

The group has also been publicly linked by cybersecurity researchers to a 2021 cyberattack that caused widespread outages at gas stations across Iran.

Israel has never formally acknowledged that it is behind the group, although Israeli media has widely reported Gonjeshke Darande as “Israel-linked.”