Opposition parties demanded Sunday that the government withdraw the Self-Defense Forces from Iraq after a 24-year-old Japanese traveler who had been abducted by militants was found beheaded.

The leaders of the Democratic Party of Japan, the Japanese Communist Party and the Social Democratic Party held separate news conferences at the Diet building within hours of the government's positive identification that the body found in central Baghdad was that of Shosei Koda.

Koda's abductors had said they would decapitate him unless the roughly 600 Ground Self-Defense Force troops in Iraq were pulled out within 48 hours. Prime Minister Junichiro Koizumi refused.

"If the SDF had not been dispatched (to Iraq), this incident would never have happened," DPJ chief Katsuya Okada said. "The current SDF mission ends on Dec. 14. We strongly demand that the deadline not be extended and the SDF withdraw."

Yoshio Hachiro, the DPJ's Diet affairs chief, called his counterpart from Koizumi's Liberal Democratic Party, Hidenao Nakagawa, and requested that the House of Representatives Budget Committee hold a special session with the prime minister attending to discuss the incident.

He also asked that the government explain the hostage case during Monday's Lower House plenary session and sessions of relevant Diet committees, also with Koizumi present.

Kazuo Shii, chairman of the JCP, charged that the "reckless war and occupation" by the United States has turned Iraq into a hotbed of terrorism.

"Japan's responsibility as a supporter is also being called into question," he said. "To avoid another tragedy, the government must make an about-face in its policy toward Iraq."

SDP leader Mizuho Fukushima, meanwhile, stressed that Koda's death was "an extension of the wrong use of military force by the U.S. and the wrong political choice by Japan."