US homeland security officials say World Cup matches will be “very secure” but have expressed concerns over potential lone wolf attacks, particularly in public areas outside official security perimeters.

Markwayne Mullin, head of the Department of Homeland Security, said on Thursday that while security measures at the 11 US host cities would be comprehensive, authorities cannot fully control against lone wolf threats.

“We feel like we’re as safe as we can possibly be. But we can’t control, you know, the lone wolf,” Mullin said during an interview on Fox and Friends.

The official highlighted particular concern for “soft areas” – public spaces before entry into official security zones – where local and state law enforcement will maintain a visible presence to ensure crowd safety.

The 2026 FIFA World Cup, which the United States is co-hosting with Canada and Mexico, opened on Thursday in Mexico with a match between the hosts and South Africa. Of the tournament’s total fixtures, 78 games will be played across US cities over 38 days.

Mullin compared the scale of the event to America’s most-watched sporting occasion, the Super Bowl. “We will have crowds bigger than the Super Bowl,” he said, adding that whilst 250 million people typically watch the Super Bowl, the FIFA World Cup is expected to draw 1.4 billion viewers globally.

Security arrangements for the tournament involve coordination between federal, state and local law enforcement agencies across all host venues.

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