Gunmen kidnapped a Japanese engineer in a highway ambush in central Iraq (search) on Wednesday, police said. A British security worker and an Iraqi colleague were killed in an attack in the same area, the U.S. military said.

It was not immediately clear if the two attacks were connected, but they were the latest in increasing violence in the days ahead of Jan. 30 elections.

The engineer, who worked at a power station in the city of Beiji (search), was traveling with two Iraqi policemen when gunmen stopped their car, killed the two officers and abducted the Japanese, said Iraqi police Lt. Shaalan Allawi.

The engineer was not identified by name and no further details were immediately available.

The British security worker and an Iraqi colleague were killed in an ambush near the Beiji power station complex, which they were helping protect, said Major Neal O'Brien, a spokesman for U.S.-led coalition forces based in the Iraqi town of Tikrit (search).

A third man, another foreign national, is still missing, O'Brien said, without specifying the nationality.

The two men, who were not identified, worked for the London-based Janusian Security Risk Management.

"We are proud of their professionalism and dedication and of the role they played in trying to help in the reconstruction of that country," said David Claridge, managing director of the firm.

"We are investigating the matter and are working with the local authorities in their efforts to locate the missing civilian."

More than 180 foreigners have been kidnapped in Iraq over the past year in an insurgent campaign to drive out those working alongside the United States and the U.S.-backed Iraqi government. At least 17 foreigners are still being held.