An 18-year-old Minnesota man has been arrested after U.S. authorities accused him of planning an ISIS-inspired attack at the Mall of America, one of the country’s largest shopping centres.

The suspect, identified as Sheikhdoon Abdullahi Mohamud, was arrested Tuesday in Richfield, Minnesota, during an undercover FBI operation, according to federal authorities and court documents unsealed this week.

Prosecutors allege that Mohamud had been under investigation for nearly two years after communications with an FBI confidential source raised concerns about his interest in extremist violence.

According to the criminal complaint, the investigation began in late 2024, when Mohamud allegedly discussed travelling overseas to join an extremist organisation or carrying out an attack in the United States. Authorities said his focus later shifted toward an attack inside Minnesota.

Federal prosecutors further allege that Mohamud expressed support for ISIS and eventually identified the Mall of America as a potential target.

Authorities said the investigation culminated in an undercover meeting on Tuesday, October 6, during which Mohamud allegedly attempted to obtain firearms and ammunition from an undercover FBI employee. He was arrested shortly afterwards.

Prosecutors said Mohamud had indicated that he wanted to carry out the alleged attack later in October during a festival at the Mall of America. The event identified in court documents is the Hmong Arts Celebration.

The FBI said the operation was intended to prevent the alleged plan from progressing to an actual attack.

U.S. Attorney for Minnesota Daniel Rosen described the arrest as the result of a lengthy investigation involving federal law enforcement and intelligence officials.

FBI Minneapolis Special Agent in Charge Christopher Dotson also said the messages attributed to Mohamud demonstrated what investigators regarded as a serious commitment to ideologically motivated violence.

Authorities said investigators had previously attempted to intervene after receiving information about Mohamud’s alleged online extremist activity. Rosen said FBI agents visited his family in 2025 to raise concerns about his possible radicalisation.

Mohamud is believed by authorities to have been born in the United States, although the federal complaint identifies Somalia as the homeland of his parents.

The case has prompted renewed attention to the challenges faced by law enforcement in identifying and disrupting potential acts of extremist violence before they occur.

Federal prosecutors have accused Mohamud of knowingly obtaining a firearm and ammunition with knowledge that they would be used in connection with terrorism. He remains presumed innocent unless and until the allegations are proven in court.

The investigation remains ongoing, while federal authorities continue to examine the alleged communications and circumstances surrounding the planned attack.

Reporting by TalkNaijaMedia