If someone is detained

Stay calm. Do not give false information — it can be used against them.
Ask where the person is being held and get their A-number (alien registration number) if possible.
You can locate someone in ICE custody with the Online Detainee Locator at ice.gov/locator.
Contact the nearest consulate — many provide legal referrals and can visit detainees.
Contact an immigration attorney as soon as possible.
Do not let the person sign a "voluntary departure" or any other agreement without a lawyer.

Source: Adapted from materials published by the Immigrant Legal Resource Center. This is general information, not legal advice. Talk to an immigration attorney about your situation.