SAPPORO (Kyodo) A senior election campaigner for a Democratic Party of Japan lawmaker was arrested Thursday on suspicion of promising to pay money to other campaigners in the Aug. 30 Lower House election, police said.

The DPJ's Chiyomi Kobayashi, who represents the Hokkaido No. 5 constituency and beat former Chief Cabinet Secretary Nobutaka Machimura, could lose her Diet seat if the arrested official, Hirokazu Yamamoto, 60, is convicted.

Yamamoto has admitted promising to pay several hundred thousand yen to about 30 people who contacted voters over the phone in support of Kobayashi between May and August in the runup to the general election, the police said.

If someone who led an election campaign on behalf of a candidate is convicted of violating the election law and receives a sentence, even a suspended one, the candidate must also be held responsible.

"It would be regrettable if (the charge) is true," Kobayashi told a news conference Thursday in Sapporo.

Yamamoto was deputy head of Kobayashi's election committee, but Kobayashi claimed she didn't meet him during the campaign and "doesn't recognize" what role he played in it.

"(Yamamoto) has just been arrested. I can't respond to speculation," she said, adding she has no intention of stepping down.

The news conference continued for more than one hour as reporters repeatedly fired questions about Yamamoto, but Norimichi Sano, head of the DPJ's Hokkaido branch, handled most of the queries while Kobayashi only nodded or looked down.

Kobayashi defeated Liberal Democratic Party heavyweight Machimura and another candidate in the constituency in the August poll.