Experts warn of ‘soft target’ vulnerabilities and intelligence gaps as federal agencies prepare to secure 78 matches across 11 cities

Fifa World Cup matches set to be held across the United States face heightened terrorism risks, with experts warning that vulnerabilities are being amplified by the US-Israel conflict with Iran and a depletion of counter-terrorism expertise within federal law enforcement.

The biggest threat stems from homegrown violent extremists, often lone actors that may have become radicalized online by extreme political views or jihadists such as the Islamic State (Isis), said four counter-terror experts interviewed.

After Guardian reports about danger to V2X employees, sources say state department raised concerns with defense contractor

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The US government has called on the defense contractor V2X to evacuate its employees from Kuwait and Iraq, warning the company that they could be targeted by Iran-backed militias, four sources said.

The intervention follows reporting by the Guardian that V2X employees were stationed at US military bases in Kuwait, and at Martyr Brigadier General Ali Flaih airbase and Erbil in Iraq. Employees claimed having inadequate protections, receiving limited communications from the company about evacuation plans and being pressured to remain in the Middle East. In Iraq, workers say they are targets of Iran-allied attacks, and one employee was killed in a night-time drone attack in March.