By Irene Klotz

CAPE CANAVERAL, Florida (Reuters) - NASA has shut down access to an online database and banned new requests from Chinese and some other foreign nationals seeking access to its facilities amid mounting concerns about espionage and export control violations, the U.S. space agency's administrator said on Wednesday.

The security measures include a complete ban on remote computer access by Chinese and some other non-U.S. contractors already working at NASA centers, agency chief Charles Bolden said at a congressional oversight hearing in Washington.

The tightening of security follows the arrest on Saturday of Chinese national Bo Jiang, a former NASA contractor. He was attempting to return to China with "a large amount of information technology that he may not have been entitled to possess," said Representative Frank Wolf, a Republican whose Virginia district includes the NASA Langley Research Center, where Jiang worked.

The FBI arrested Jiang at Dulles International Airport outside Washington, where he had boarded a flight to Beijing, court papers provided by Wolf's office show.

Jiang was arraigned on Monday in U.S. district court in Norfolk, Virginia. A detention hearing is scheduled for Thursday.

He is charged with lying to federal law enforcement agents about computer hardware he planned to take with him to China, the court documents show.

Wolf, who chairs the House Appropriations subcommittee on commerce, justice and science, identified Jiang last week during another hearing on possible security lapses at NASA field centers.

"We know that China is an active, aggressive espionage threat," Wolf, a longtime China critic, said during Wednesday's hearing.

"A recent White House report said that the technologies NASA works on - aerospace and aeronautics - are those that the Chinese have most heavily targeted," Wolf added.

Original post:

NASA steps up security after arrest of former contractor