WASHINGTON - Evidence of an unrelenting campaign of cyberstealing linked to the Chinese government is prompting the Obama administration to develop more aggressive responses to the theft of U.S. government data and corporate trade secrets.

The administration is expected to announce today some new measures, including possible fines and other trade actions against China or any other country guilty of cyber-espionage.

The Chinese government denies being involved in the cyberattacks cited in a cybersecurity firm's analysis of breaches that compromised more than 140 companies.

The Virginia-based cybersecurity firm has tied a secret Chinese military unit in Shanghai to years of cyberattacks against U.S. companies.