Mitutoyo Corp., a precision instrument maker at the center of an export scam linked to weapons of mass destruction, has exported some 10,000 sensitive devices, most of them illegally, since around 1995 and in the process may have helped North Korea and Iran go nuclear, investigative sources said.

The Metropolitan Police Department's Public Safety Division is investigating the possibility that some of these instruments were exported to North Korea, Iran and other nations suspected of developing atomic weapons via a nuclear black market formerly run by Pakistani physicist Abdul Qadeer Khan, the sources said.

In addition, police are investigating suspicions that a Mitutoyo three-dimensional precision measuring machine of a different type that went to Libya via Khan's smuggling network was exported to an Iranian firm suspected of links to Iran's nuclear program, they said.