Prosecutors say Mario Santoyo, 38, of Chicago brought a knife into the building last month, prompting the standoff.
In court Tuesday, a judge ruled that Santoyo will be released into the custody of his sister, with an ankle monitor.
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He's also being ordered to stay away from any federal buildings, except for court appearances.
And he will receive psychiatric assistance.
Santoyo is charged with felony possession of a dangerous weapon in a federal facility with intent to use the weapon in the commission of a crime, officials said.