(CNN) -- A 20-year-old Jordanian man was sentenced Tuesday to 24 years in federal prison after he was caught, in an FBI undercover operation, trying to use a truck bomb to destroy the 60-story Fountain Place office building in Dallas, Texas, authorities said.

Hosam Maher Husein Smadi pleaded guilty in May in U.S. District Court in Dallas to attempted use of a weapon of mass destruction, which carries a maximum life sentence.

"The court's sentence of Mr. Smadi sends a clear message that there is a serious price to be paid by those who may be willing to carry out acts of violence in this country to further the terrorist cause," Assistant Attorney General David Kris said.

After entering the United States illegally and living in Texas, Smadi drew the attention of authorities for his comments on an extremist chat site, and undercover law officers contacted him while they posed as members of an al Qaeda sleeper cell.

He told agents he wanted to commit violent jihad and was a soldier of Osama bin Laden, but authorities found no tie between him and any terrorist group.

On September 24, 2009, Smadi was provided with a truck with an inert bomb that he believed was active, and he parked the vehicle in a garage under the office building, court documents said.

Smadi activated a timer, locked the truck and walked to a car with an undercover agent. They drove a safe distance to watch an anticipated explosion, court papers said. Smadi used a cell phone to try to detonate remotely what was a defused bomb, documents said.