Tetsuya Yamagami, the man arrested for the assassination of Japan’s former Prime Minister, Shinzo Abe, told police he held "a grudge" against a religious group that he believed the leader had promoted.

Yamagami, 41, reportedly told the authorities that his mother went bankrupt after making a “huge donation” to the Family Federation for World Peace and Unification, also known as the Unification Church.

Nara Prefectural Police said the suspect blamed his mother’s financial issues on the religious group and intended to kill Abe based on the assumption that the former prime minister was affiliated with the Unification Church.

“My mother got wrapped up in a religious group and I resented it,” Yamagami was quoted as saying.

Tomihiro Tanaka, the president of the Japanese branch of the Unification Church, confirmed on Monday that Yamagami’s mother is one of its members. He also noted that Yamagami and Abe were not members.

The suspect’s mother reportedly became a member of the church in 1998 before going bankrupt in 2002. She stopped attending from 2009 to 2017 but reconnected with other church members around two to three years ago.

According to Tanaka, she has been attending church meetings and events around once a month for the past six months

Tanaka reportedly refused to comment on how much the suspect’s mother donated, and he denied that she was forced by the church to donate money.

On Monday, Nara police said they discovered bullet holes at a facility run by the church. Yamagami reportedly admitted to firing practice rounds the day before Abe was fatally shot in the chest and neck while delivering a speech at a campaign event in the Japanese city of Nara on Friday.

Several improvised guns were seized from Yamagami’s apartment, the police said on Friday. The firearm he reportedly shot Abe with was a double-barreled, homemade gun that measured approximately 16 inches long and 7 inches wide.

While the Unification Church said it did not have a direct relationship with the former Japanese leader, Tanaka admitted that Abe expressed support for its global peace movement.

Abe previously spoke at an event hosted by a Unification Church-affiliated organization last September.

Politicians from other countries, including the U.S., were also reportedly involved in the event. Abe delivered a speech in which he praised the organization for its “focus and emphasis on family values.”

Meanwhile, other affiliates of the church reportedly continue to draw in various Japanese lawmakers to their events.

In 1954, the Unification Church was founded in South Korea by Sun Myung Moon, who was allegedly an anti-communist and self-declared messiah.

The church established other branches overseas, including its Japanese branch in the late 1950s. The church found “common cause” with right-wing politicians in Japan, such as Abe’s grandfather Nobusuke Kishi.

Around 600,000 people in Japan are members of the church and have reportedly helped it generate billions of dollars in income.

Moon helped to create a multi-billion-dollar corporate empire with ventures such as the Washington Times, United Press International and the New Yorker Hotel in Manhattan, before his death in 2012.

Critics and former members have identified the church as a cult; however, the church has denied previous accusations and claims to be legitimate.

An investigation of Yamagami’s background and motives is currently ongoing.