A pro-Iranian group that holds two American hostages said Thursday the captives "will be part of a comprehensive retaliation" for a U.S. missile attack on an Iranian jetliner in the Persian Gulf.

The Revolutionary Justice Organization, which holds American hostages Edward Austin Tracy and Joseph James Cicippio, made the threat in a typed statement that was delivered to the office of a Western news agency in Moslem west Beirut early Thursday.The statement said the 290 people aboard the Iranian jetliner that was shot down in error Sunday by the USS Vincennes were "sacrificial victims for the presence of the American warships in the gulf" and it will not be difficult for the group's supporters to "choose the right targets."

"Let everybody know that all the strong cards are still in our hands, including the hostages affair, which will be part of a comprehensive retaliation that will force the murderers to pay the price," the statement said.

The group also threatened to attack targets of nations that supported the U.S. stand on the accidental shooting. "All who backed them are partners in the crime," the statement said.

The statement was accompanied by a blurred photocopy of Tracy's passport, which was distributed previously by the same group.

Tracy, 55, a convert to Islam, was kidnapped Oct. 21, 1986, in west Beirut. Cicippio, 56, deputy comptroller of the American University of Beirut, was abducted Sept. 12, 1986, after leaving his apartment in the Moslem sector of the city.

The group charged Cicippio was a spy in a statement released after his kidnapping.

Thursday's threat was the second against American hostages since the Vincennes misidentified an Iranian Airbus A300 Sunday as an Iranian F-14 and fired two missiles at the jetliner as it flew across the Persian Gulf with 290 people aboard, most of them Iranians. At least one missile struck, destroying the plane, its passengers and crew.

A caller claiming to represent the pro-Iranian Islamic Jihad said Tuesday the group would execute one of its hostages later in the day. Another caller claiming to speak for the group later told the Moslem Voice of the Nation radio the slaying was postponed at the request of Iran's powerful parliament speaker and armed forces chief Ali Akbar Hashemi Rafsanjani.