Transport minister Kazuo Kitagawa and 13 counterparts agreed Friday in Tokyo to work together to fight terrorism, a threat Japan is already addressing by bolstering security to prevent attacks on its transportation networks.

The government began tightening security at air and sea ports after the Sept. 11, 2001, attacks on the United States. But despite its efforts to prevent terrorists from entering the country, at least one person, a Frenchman allegedly linked to the al-Qaida terrorist network, slipped through on a fake passport several times in 2002 and 2003.

"Japan is still lagging behind in counterterrorism measures," said Katsuhiko Furukawa, a senior fellow specialized in safety and security issues at the Research Institute of Science and Technology for Society.