What are the procedures to donate U.S as an forbidden immigrant?

They were asked to leave U. S for more than 3 years ago (not court order, it be a letter sent by the INS). Now they intend to leave the U.S. with expired Visas and passport. What are they going to own to do? Should they contact the INS and ask for something or they can simply just need to buy an air plan tickets and free to do so? Thank you terribly much!
PS: If they left U.S, will they enter the 10 years ban and what are some steps they should do in casing they want to come back to the U.S?
Answers:   
There should be no problem at all leaving the USA, expired visa or not. Thousands of those do it every month at the border with Mexico. US immigration officials do not check those who are leaving, and the possessor (e.g. airline) only checks to ensure that the person leaving have valid credentials to enter the country to which they are going (so they don't have to pay for bringing them back).

You will have to ask the INS something like the rules which apply to any reentry to the US. However, it is worth remembering that since they will not be checked on the way out, nobody really knows when they left except themselves.
they can move about back to us as long as they get the passport stamped on an earlier date and dont submit their i-94 at the time of exit.
you should know someone at the airport at the time of arrival and bring it back dated stamped, then you can aplly for a canadian visa and from there dance back to us.
i hope you will be able to do it, if not contact me back they start from there on 9347572909.



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