Anonymous claims to have hacked a server belonging to agricultural firm Monsanto and exposed 2550 names, addresses phone numbers and email addresses reportedly linked to the company.
In a statement the collective said it had “blasted their web infrastructure to **** for two days straight, crippling all three of their mail servers as well as taking down their main web sites worldwide."
Monsanto was unavailable to confirm the breach.
Anonymous did not detail how the breach was conducted however Sophos senior security advisor Chester Wisniewski said that it have established an IRC channel on the compromised host on which port 6666 was open.
It said it would also open an online wiki to distribute the stolen Monsanto information.
In a separate post on website pastee.org it claimed that the OpsMonsanto Twitter account was attacked with attempts made “to access/change the password … as well many failed login attempts on two corresponding email accounts.”
It said a PayPal account “used to finance the operation” was frozen.
“Somebody, most certainly, is mad at us.”
In retaliation, the group had updated the leaks with previously redacted phone numbers.
The group, which had this week stolen account detail held by consultant Booz Allen Hamilton, announced "Project Tarmaggedon" in which it would target oil companies Exxon Mobil, Canada Oil Sands, Imperial Oil and the Royal Bank of Scotland.
It claimed members would protest along a major US East-West Highway against a major oil exploration project in Canada.
"Anonymous will not stand by idly and let these environmental atrocities continue. This is not the clean energy of the future that we are being promised,” it said in a statement.