Illustration file picture shows a man typing on a computer keyboard in Warsaw Thomson Reuters DENVER (Reuters) - U.S. officials are assessing whether and how they could impose visa restrictions to prevent Chinese hackers from attending the popular Defcon hacker conference in Las Vegas and similar events, a senior administration official said on Saturday.

The official said the U.S. government was considering whether to impose such visa restrictions and other measures to maintain pressure on China after the United States this week charged five Chinese military officers and accused them of hacking into U.S. nuclear, metal and solar companies to steal trade secrets.

China has denied the charges, saying the U.S. grand jury indictment was "made up" and would damage trust between the two nations.

U.S. officials are weighing a range of options if China doesn't begin to acknowledge and curb its corporate cyber espionage, the official said.

The Wall Street Journal on Saturday reported that those options could include releasing additional evidence about how the hackers conducted their alleged operations, and imposing other business and financial restrictions on those indicted or people or organizations associated with them.

(Reporting by Andrea Shalal; Editing by Stephen Powell)