Gyoun Imadegawa, chief priest of Hieizan Enryakuji on the outskirts of the ancient capital, Kyoto, and six other board members, stepped down Thursday for damaging "faith" in the temple, said Enryakuji spokesman Jakuho Mizuo.
About 80 members of Yamaguchi-gumi, the largest underworld syndicate in Japan, attended the April 21 memorial for its past bosses at the temple's Amidado Hall, said Mizuo, one of the temple officials who resigned.
"We are very sorry and extend our heartfelt apology to all the people who are in support of the Enryakuji temple," the temple said on its Web site.
The 1,200-year-old temple said it had been "extremely careless" in allowing a crime gang to use its facilities when most of the country has been calling for the elimination of such groups.
"The biggest problem is that we lacked due consideration," said Mizuo.
It was the first time Enyakuji has allowed a known underworld syndicate to hold a memorial in the compound, Mizuo said.
Enryakuji, the most important temple in the Tendai sect of Buddhism, will send a letter of apology to the sect's 3,000 other temples in Japan, he said.
Yamaguchi-gumi, Japan's largest underworld syndicate, is based in Kobe and has 41,000 members, accounting for about 47 percent of all gangsters in Japan, according to the National Police Agency.
Japan's gangsters -- commonly called yakuza -- are among the world's wealthiest, bringing in billions of yen a year from extortion, gambling, the sex industry, guns, drugs, and real estate and construction kickbacks. They are also involved in stock market manipulation and Internet pornography. (AP)