Coca-Cola, ArcelorMittal and Chesapeake Energy among companies that failed to disclose computer attacks.

Coca-Cola, ArcelorMittal and Chesapeake Energy among companies that failed to disclose computer attacks.

Comment group targets oil companies, patent law firms and investment banks.

Comment group targets oil companies, patent law firms and investment banks.

China-based groups have engaged in global industrial espionage for years.

China-based groups have engaged in global industrial espionage for years.

Hackers believed to be connected to foreign government.