Adani has threatened legal action against an activist group that is encouraging its supporters to infiltrate the miner by signing up for jobs with its proposed Queensland mining project.

A law firm acting for Adani wrote to the Galilee Blockade on Tuesday to signal it would take “all steps available to it” should the activists obtain confidential information from employees.

This included seeking a “permanent injunction … plus costs” from a court to stop Galilee Blockade using the information, as well as suing the group for “inducing a breach of contract” by an employee.

Galilee Blockade last week emailed almost 12,000 supporters asking them to register interest in a career with Adani, in order to gain “inside information on Adani and their friends” to help “direct action tactics to stop them”.

A partner from Herbert Smith Freehills, in a letter seen by Guardian Australia, said Adani “respects citizens’ rights to agree with, or to oppose, commercial developments using lawful means”.

“However, the conduct intimated in the Galilee Blockade is unlawful, and quite reasonably and appropriately will take legitimate steps to protect itself from these threatened unlawful activities,” the lawyer said.

He said that Adani’s employee contracts contained confidentiality provisions and the company took any breach “very seriously”.

Any worker that breached or tried to breach these obligations would face a possible injunction by Adani “together with costs and damages” claims.

The lawyer said that “even if Galilee Blockade obtained confidential information from an Adani employee” it had a “duty not to use or disclose that information”.

If the activist group “persuaded an Adani employee to disclose such confidential information in breach of the obligation of confidence, then Galilee Blockade would also be liable to Adani in tort for inducing a breach of contract”, he said.

The lawyer said Adani would be “updating its processes so that anyone registering with it or applying for a job will be made aware of the legal implications of intentionally breaching their obligations of confidence under your inducement”.

He said that “as a result of this letter Galilee Blockade now has actual knowledge that the conduct intimated in its flyer would result in the employee breaching her/his employment contract”.

Ben Pennings, the spokesman for the Galilee Blockade, said in an online video message to supporters on Tuesday: “It looks like Adani are on the attack.”

He said the letter was “just bullshit threatening stuff which will go between their lawyers and our lawyers”.

“And the simple thing is and the simple message from me is, as the person who got this letter, is fuck you, I’m not going to do what you tell me,” Pennings said.

“The simple message from hundreds and hundreds of climate activists around the country that we’ve met on our road tour the last few days, is fuck you, we’re not going to do what you tell us.

“We’re the resistance. We don’t listen to you. We don’t do what you say.

Pennings said the letter meant “we know who Adani’s lawyers are now, so that’s another target for us because we’re targeting anyone who’s in bed with Adani”.

Adani’s Carmichael mine has political support in Queensland from both major parties, who cite the project as an economic driver for stalling regional economies.

But opposition to the largest proposed coalmine in Australia has become a rallying point for the environmental movement, as well as marine scientists concerned about impacts on the Great Barrier Reef and traditional owners who oppose the project.



Galilee Blockade has claimed its campaign, using civil disobedience to target Adani and related businesses, would be international in scope and “dwarf” the Franklin river campaign, a previous high point of environmental protest in Australia.