US 'on war footing' as Iran's chilling vow for revenge stokes domestic terror fears

US FBI director Kash Patel issued a grim terror warning in the wake of the joint US-Israel attack on Iran, as the destabilised regime vowed to enact revenge for its slain supreme leader.

Iran launched a swift and heavy offensive in response to the strikes, as missiles targeted US military bases in the Gulf region.

In response, Patel announced he had placed counterterrorism and intelligence teams on "high alert" and had mobilised all assisting security assets, while assuring citizens that teams were working 24/7 to disrupt any threats in the US.

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The chilling promise of "intense" retaliation has sparked fears in Washington over potential attacks on American soil.

US Defence Secretary Pete Hegseth yesterday declared that America was prepared and "ready" to respond to domestic threats levelled by the Iranian regime.

"This is a regime that seeks to export that ideology, that seeks to export terror," Hegseth said.

"We're ready for that."

Multiple US outlets have reported that the FBI and Department of Homeland Security had been placed on "war footing" in anticipation of retaliatory action.

Former FBI counterterrorism official Matthew Levitt told USA Today that if there was ever a time for Iran to launch attacks abroad, "it would be now".

"Iran has developed this capability to carry out attacks abroad over many years," Levitt said.

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The FBI is investigating Sunday's Texas bar shooting, which left two people dead and wounded 14, as a potential terrorist act.

The gunman, identified as 53-year-old Ndiaga Diagne, was also killed in the attack.

While the shooter's motive still remains unclear, FBI Acting Special Agent in Charge Alex Doran said agents had identified potential terrorist ties.

"Obviously, it's still way too early in the process to determine an exact motivation, but there were indicators on the subject and then his vehicle that indicate a potential nexus to terrorism," Doran said.

Australia's official government advice for travellers heading to the US remains unchanged.

Visitors have been warned to avoid areas where demonstrations and protests are occurring over the potential for unrest and violence.

The latest Smartraveller advice also notes there is a "persistent threat of mass casualty violence and terrorist attacks".

"On 5 June 2025, the FBI and Department of Homeland Security issued an alert highlighting potential public safety concerns related to ongoing threats to the Jewish and Israeli communities," the advice reads.

The US has remained on a heightened threat level since the Trump-led strikes on Iran in June last year and Homeland Security warned that the risk of violent extremism on home soil would only increase if Iranian leadership called for retaliatory attacks.

"The ongoing Israel-Iran conflict could contribute to US-based individuals plotting additional attacks," Homeland Security said in a statement in June.

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