Thousands of Orthodox Jews prostrated themselves in mourning at the remnants of the Wailing Wall of the Second Temple Thursday, vowing to stop Mormons from building an academic center on the Mount of Olives.

The demonstration followed a rare press conference Wednesday in which Israel's two chief rabbis charged that the $15 million building Mormons plan to construct would be used as a base for proselytizing.

Officials of the Church of Jesus Christ of Latter-day Saints deny the charges, saying the center was designed as a Near East studies department of Brigham Young University in Salt Lake City.

Rabbis Avraham Shapiro and Mordechai Eliyahu said in a statement issued at their news conference that the seven-story building on a plot overlooking the holy city would be "a terrible wound upon the soul of the Jewish nation."

"We will not let our enemies set up a center of venom and apostasy opposite the Temple Mount," proclaimed a banner strung across a stone wall in the plaza facing the giant stones of the Wailing Wall.

The Mormons, who won the support of Jerusalem Mayor Teddy Kollek in their 12-year battle for a permit to build the center, began contruction last year.

A public campaign by Yad Le'achim -- Hebrew for "a hand to the brothers" -- brought the issue to the attention of a parliamentary committee, which is reviewing the building permits.

A Yad Le'achim organizer, predicting that the missionary work of the Mormons will begin the minute the first students arrive, said his group will "make every effort to block the construction of the Mormon Center."

A group of Catholics and Protestants called a news conference last week to charge that the Mormons are a cult and not true Christians.

Extremist Rabbi Meir Kahane, a Knesset member who has vowed to expel all Arabs from Israel and the occupied territories, told the Mormons on Wednesday, "Get out or we will throw you out."

The writings of Joseph Smith, the 19th century American founder of Mormonism, link the church's origins to the 10 lost tribes of Israel.

Some 200 Brigham Young students come to Jerusalem each year, studying in rented classrooms. The new center will allow the university to double its program in Israel, Mormon officials said.