A U.S. computer security firm says the Chinese military has resumed cyber attacks on American companies after a hiatus.
Mandiant, which accused China of cyber attacks in a February report
, says a Chinese army unit recently broke into the computer systems of more than 100 companies to steal trade secrets.
It says the attacks started again just days after Chinese officials told Secretary of State John Kerry in Beijing last month that they are willing to open cyber security talks with the United States. But China has denied attempting to steal U.S. trade secrets and says it has been a victim of American computer hackers.
Mandiant chief security officer Richard Bejtlich says China is using the same equipment it used in the earlier attacks because many U.S. companies still have no defense against it.
Bejtlich says the U.S. needs to impose new sanctions on China.