(CNN) -- Eight Ann Arbor, Michigan, schools were under lockdown Thursday morning for over two hours as police searched for an armed man who robbed a nearby bank, police said.
Lake Trust Credit Union was robbed just minutes after it opened Thursday morning, police said.
"He entered the bank, ordered everyone to the floor," said Ann Arbor Police Lt. Angela Abrams. "He had a handgun, grabbed the manager, and ordered the manager to assist him."
The robber grabbed the cash and ran out a rear door, Abrams said.
Police tracking dogs "had negative results" in finding the fugitive, she said.
Police lifted the lockdown order for the schools two hours later, she said.
Another Ann Arbor bank robbery prompted the lockdown of nearly a dozen schools last week, including several onThursday, Abrams said.