United States immigration authorities had detained Pakistan President Pervez Musharraf's nephew for more than two weeks for visa violation.
Aamir Javed Musharraf, who was detained on February 19 and released on Friday, could be deported to Pakistan.
He was arrested in Memphis, Tennessee, when he went to register at a local immigration office under a programme requiring thousands of visiting men from 25 mostly Muslim countries to be photographed and fingerprinted.
Aamir was found to have an expired tourist visa from 1994.
The authorities did not know his place of employment or any other details of his stay in the US, The Washington Times reported.
The Immigration and Naturalisation Service developed the programme after the 9/11 attacks as part of a plan to tighten US borders.