A 27-year-old man is in custody after he allegedly made threats to people attending a march for justice in Dearborn, Michigan, on Saturday, police said.

The Garden City, Michigan, man was arrested "within hours" after he allegedly made threats to harm people at the Arba'een Procession. According to the Dearborn-based nonprofit Karbalaa Islamic Educational Center, the event honored Imam Hussain, a prominent figure in Islam.

Dearborn Mayor Abdullah Hammoud and Police Chief Issa Shahin released the following joint statement on Saturday in response to the alleged threats:

"When someone threatens violence against our community, we will act swiftly and decisively. There is zero tolerance for threats of this nature, and anyone who attempts to sow fear or division will be held fully accountable. The safety and unity of our community will always come first."  

The Dearborn Police Department said it's constantly monitoring social media and other platforms for threats of violence.

Investigators are looking into the alleged threats.

The Shia Muslim Foundation, a nonprofit supporting the civic rights of American Shia Muslims, says it's "deeply alarmed" by the alleged threats.