Tokyo police turned over to prosecutors Thursday their case against a former Nikon Corp. researcher who is suspected of giving a Nikon device under development related to fiber-optic communications to a Russian official in Tokyo last year.

The Metropolitan Police Department's Public Security Division also handed prosecutors their case against the Russian official, a 35-year-old member of the Russian Trade Representation office in Japan.

The division suspects the Russian, who has left Japan, may have wanted to apply the civilian-use device to military-related technology. The 47-year-old researcher quit Nikon in March.

The device, a variable optical attenuator, is used to help stabilize transmissions in long-distance fiber-optic communications.

The employee is suspected of taking the device from a Nikon laboratory in February last year and handing it to the Russian at a Tokyo restaurant at the latter's request. The names of both individuals were not provided.

Police believe the employee received cash from the Russian and was being treated at the restaurant, they said.

The two met more than 10 times at a bar and other places and the Russian apparently received a technical paper written by the Nikon employee, and asked for other devices and technological information, including that for an infrared-ray sensor system, according to the sources.

The Russian Trade Representation office declined comment on the case.

Nikon released a statement expressing regret for the incident and promising to fully cooperate with the probe.