From this:

[Hosam Maher Husein Smadi], a Jordanian national, was arrested Thursday after federal officials said he placed what he believed to be an explosives-laden truck in a parking garage beneath the 60-story Fountain Place tower in Dallas. He was charges with trying to detonate a weapon of mass destruction and faces up to life in prison if convicted.

...In Jordan, Smadi's father insisted his son is innocent. He said Smadi and his brother, Hussein, 18, came to the United States in 2007 on a student visa. U.S. immigration authorities did not comment on Smadi's status, citing confidentiality.

From this:

...An affidavit in the case filed by Thomas D. Petrowski, FBI supervisory special agent in Dallas, said that Smadi had an Alien Registration Number issued by the U.S. Department of Homeland Security. Spokesmen at DHS would not discuss Smadi’s case. However, DHS issues Alien Registration Numbers both to aliens who originally enter the U.S. legally and to aliens who originally enter the U.S. illegally and are later encountered by DHS.

State Department Spokesman Andy Laine told CNSNews.com that the State Department would not comment on whether or not Smadi was given a visa to enter the U.S. because visa records are confidential...