Gov. Mark Dayton condemned the attack, calling it a hate crime and an act of terrorism.
"What a terrible, dastardly, cowardly, terrible act this was that was committed," Dayton told the Star Tribune. "This is an act of terrorism. This is against the law in America."
The FBI is investigating. They said the blast was caused by an improvised explosive device.
"We feel like it's much deeper and scarier than like something random," Omar said Sunday. "It's so scary."
The reward for information leading to an arrest is $24,000, said Asad Zaman, director of the Muslim American Society of Minnesota.
The Associated Press contributed to this report.