An Israeli advocacy group won a $323 million judgment in a U.S. court against Iran and Syria for supporting Palestinian militants that killed an American teenager and ten others in a 2006 bombing, the group's director said Tuesday.

Nitsana Darshan-Leitner of the Shurat HaDin Israel Law Center that represents victims of Palestinian violence said Tuesday that the group had won courtroom victories against Iran but never before against Syria.

The center was representing the family of 16-year-old Daniel Wultz of Florida, who was among 11 killed when an Islamic Jihad suicide bomber set off his explosives at a Tel Aviv restaurant six years ago. Daniel's father was severely injured in the attack.

Darshan-Leitner said that Iran supports the Islamic Jihad movement financially while Syria had granted the group a haven to train in its territory.

U.S. District Judge Royce Lamberth said in the Monday ruling, "When a state chooses to uses terror as a policy tool - as Iran and Syria continue to do - that state forfeits its sovereign immunity and deserves unadorned condemnation. Barbaric acts like the April 17, 2006 suicide bombing have no place in civilized society and present a moral depravity that knows no bounds."

An American lawyer representing Syria argued the case should be dismissed on the grounds of "sovereign immunity" but the court dismissed it.

Darshan-Leitner said there is a good chance for the victim's family to get compensation through frozen Syrian assets held by the U.S.

"For the first time an American court is holding the government of Syria accountable for its decades-long support of terrorism," she said.