The former South Korean military officers who allegedly kidnaped Unification Church acting leader Col. Bo Hi Pak in September threatened to burn down the church's headquarters last month in Irving, N.Y., after Pak failed to transfer $500,000 to a Swiss bank as promised, federal prosecutors in New York said yesterday.

The alleged kidnapers had forced Pak to make tape recordings giving assurances that he was safe while he was held in a New York farmhouse where the FBI said he was handcuffed to a bed, tortured with electric shocks and threatened with death, according to court documents.

Some of the new allegations were spelled out yesterday in a six-count indictment issued by a federal grand jury in New York against Yung Soo Suh, who has been described by the FBI as the ringleader of the conspiracy. Suh, who was arrested last Thursday in Tokyo, was charged with extortion, kidnaping and other counts.

The indictment did not disclose new information about the backgrounds of the six arrested South Koreans.

Don Paragon, a lawyer for one of the South Korean defendants, Gen. Sang Whi Nam, disputed the government's contention that the plot was an attempt to extort money and said yesterday that it arose out of an internal church dispute.

"There was a dispute over the direction of the church," Paragon said in a telephone interview. "There have been many Koreans that dislike the way the church was functioning, the selling of candy on the streets, the solicitation of money that seemed to bring down the reputation of the church.

"These people thought the church should operate schools, should operate kitchens, things of that social character . . . . They thought the church should be more pro-American in its operations and act more in the values of this country . . . . Mr. Pak may not have wanted these changes made."

Paragon also said that Nam had once been described by the Rev. Sun Myung Moon, founder of the Unification Church, as his "savior" for helping to rescue him from a prison camp in North Korea.

But Unificiation Church official Joy Garratt said yesterday that this was "absolutely false" and that "as far as we are concerned this is not a church matter."

Garratt confirmed that Nam had been living at a room in church headquarters in the New Yorker Hotel in New York City while studying church theology and programs this year.

Moon, the Unification Church's spiritual leader, began serving an 18-month sentence on tax-evasion charges in July. Pak has been running the church in Moon's absence. Pak also is chairman of News World Communications Inc., which owns The Washington Times and New York Tribune newspapers.

According to the indictment of Suh, Pak was abducted at gunpoint outside the Grand Hyatt Hotel and driven to the upstate farmhouse where he was held between Sept. 23 and 25.

After being tortured with electric shocks, Pak agreed to transfer $500,000 from an account at D.C. National Bank to a numbered Swiss bank account, according to government sources. The abductors then released Pak and drove him to LaGuardia airport, where he flew to Washington, D.C., on Sept. 25. That day, Pak went to the bank and made arrangements to transfer the money to Switzerland, but the transfer was not made.

The FBI entered the case when church officials, worried over Pak's absence, called the bureau. Agents contacted Pak after he was freed and, according to the FBI, Pak cooperated in the investigation. According to informed sources, Pak subsequently asked the bank to cancel the transfer.

According to court records filed by the FBI, Suh phoned Pak from Tokyo on Oct. 25 and threatened to burn down the church's complex in Irving, N.Y., which has been the church's international headquarters and Moon's residence. Before any of the threats could be carried out, the FBI arrested Suh in Japan and the other five in the United States.