The city assembly of Arida, Wakayama Prefecture, on Thursday approved the resignation of Mayor Mitsuo Tamaki, submitted after several senior city officials were charged with election law violations.

Several senior city officials had been accused of assisting the election campaign of Lower House lawmaker and former Transport Minister Toshihiro Nikai in his successful re-election bid for the Wakayama No. 3 constituency in the June 25 general election. The Public Offices Election Law bans civil servants from using their status to assist in election campaigns.

In the Nikai case, three figures, including deputy mayor Morimasa Okada and Kazuya Oura, head of the city's general affairs section, were arrested last month on suspicion of violating the law by distributing membership forms for Nikai's political support group to their subordinates at the city office.

Many of the subordinates -- mainly section heads or above -- passed the forms on to their subordinates, police said. Twenty city officials have so far received some form of criminal punishment in connection with the case.