Most Japanese hold deep reservations about plans to send non-combat troops (search) to Iraq, according to an opinion poll released Monday after two of its diplomats were shot to death there.

About 79 percent of respondents believe sending troops to help rebuild Iraq would make Japan a greater target of terrorism, the poll conducted by the Mainichi Shimbun newspaper showed. It also found support for Prime Minister Junichiro Koizumi (search) was plunging.

It was published Monday as Japan's Foreign Ministry was to hold a memorial for envoys killed in a roadside ambush on Saturday.

Senior ministry officials held an emergency meeting early Monday to discuss the ambush. Though chief Cabinet spokesman Yasuo Fukuda said Sunday the attack was most likely an act of terrorism, the government was still investigating who carried it out and why.

The men were Japan's first fatalities in Iraq since the U.S.-led war began in March.

Details of the ambush remained sketchy, but the news renewed public jitters about Koizumi's pledge to provide non-combat troops to help with humanitarian and other non-combat support. Koizumi has vowed that the attack would not change his plans.

Fears about being made a target rose two weeks ago when an alleged Al Qaeda operative, Abu Mohammed al-Ablaj (search), warned that Tokyo "is the easiest place to destroy." He reportedly made the threat in an e-mail statement sent to the London-based Al-Majalla newspaper.

In the Mainichi Shimbun poll, more than 80 percent said they had reservations about sending troops to Iraq. Forty percent said a deployment should occur only after the security situation stabilizes, while 43 percent were against any deployment regardless of timing.

The same survey noted support for Koizumi's Cabinet fell 14 percentage points in the last month to 42 percent.

The nationwide poll of 1,036 people was conducted by telephone on the weekend, with a quarter responding after news of the attack was reported early Sunday. No margin of error was provided.