Three-and-a-half years ago, Israeli reserve Gen. Doron Almog was forced to flee Britain just after landing in London. He had been tipped off about a surprise warrant for his arrest issued by a British magistrates court. The charge: war crimes.

Now, as the recent Gaza war stirs up more accusations of offenses, the Jewish state and international human rights advocates are gearing up for more potential criminal cases against military officers and political leaders in Europe and possibly elsewhere.

But instead of international tribunals or the Israeli justice system, the main venue for the cases is expected to be European domestic courts that cite a legal approach known as "universal jurisdiction" that allows for the trial of cases of heinous acts, torture, or war crimes that allegedly occur outside their own borders.

Israelis consider the threats part of an ongoing political witch hunt. Palestinians and humanitarian activists, on the other hand, see the domestic courts as the only forum to argue whether war crimes were committed.

"The systems in place across a number of countries will be tested.... We have legal teams working across and beyond European countries" on behalf of Palestinian plaintiffs claiming war crimes, says Daniel Machover, an Israeli-born British lawyer who works in coordination with the Gaza-based Palestinian Center for Human Rights and pushed for Mr. Almog's arrest in 2005. "There's no other way a country under occupation or a land under occupation can seek justice."

Mr. Machover also helped bring before a Spanish national court the case of the Israeli assasination of a Hamas military chief in 2002.

That bombing allegedly killed more than a dozen civilians in a Gaza neighborhood.

Just last week, a Spanish judge announced an investigation, sparking tension between Israel and Spain, and spurring more speculation in Israel of war crimes efforts.

Dogged by a series of allegations ranging from targeting civilian locations to preventing the evacuation of noncombatants, Israel's government in recent weeks reaffirmed a commitment to offer legal defense to soldiers and politicians implicated in the cases. It has also decided to keep the identities of soldiers secret to protect as many as possible from prosecution.

According to Palestinian officials, more than 1,300 Gazans were killed and thousands wounded during the three-week Israeli offensive against Hamas last month. The number of noncombatants included in those figures is disputed. Only 13 Israelis were killed, most of them were soldiers.

In her debut address as the US ambassador to the United Nations, Susan Rice called on Israel to investigate the behavior of its military in the recent Gaza war and accused Hamas of its own violations for firing rockets at Israeli towns and working out of civilian areas.

An Israeli investigation is unlikely given the conviction by most Israelis that the Israel military did its best to limit injury to civilians. Israel and the US say Hamas has broken international law by shooting rockets at towns and cities and using Palestinian civilian areas as a base.

Ironically, Israel was one of the first countries to invoke the principle of universal jurisdiction when its court system asserted its right to try Nazi chief Adolf Eichmann for crimes against humanity and war crimes during World War II.

Neither Israel nor the Palestinians, however, are parties to the treaty that set up The Hague-based International Criminal Court, making it difficult to mount a war crimes trial in that venue. Instead, legal challenges to Israeli behavior have been made in domestic courts in Europe rather than international tribunals.

One Israeli legal expert dismissed the effort to try the war crimes abroad as an extension of a "media war" against the Jewish state for the Gaza operation. Daniel Reisner, the former head of the Israeli military's international division, says universal jurisdiction is being used to pursue allegations against Israel only and not Hamas.

"The danger to Israel now are those countries that have extra territorial jurisdiction that don't have a nationality requirement," says Mr. Reisner. "The question is whether that is a major danger or a minor danger."

A Belgian court considered in 2001 an indictment of former Israeli Prime Minister Ariel Sharon for his role in alleged massacres during the Israeli invasion of Lebanon in 1982.

But broad application of universal jurisdiction by third-party national courts without links to the alleged perpetrator or victims of the war crimes is a relatively recent development, and some European legal experts say it hasn't gained traction.

Belgian lawyer Michael Verhaeghe filed charges against Mr. Sharon – a legal effort that awakened Israelis to the threat of war crimes prosecution in local European courts. He finally convinced the Belgian Supreme Court to give his case jurisdiction and standing on a 1993 national statute, but the legislation was later revoked by the Belgian parliament.

The number of states in Europe and elsewhere that have the kind of universal jurisdiction needed to try war crimes by combatants of other wars in their own courts is in decline, he said. Still, Mr. Verhaeghe believes the Israeli soldiers, if they have committed war crimes, "can't consider themselves as untouchable and safe as before."

Neither of the cases ever went to trial.

On Jan. 29, however, a National Court of Spain judge ordered an investigation into Israeli actions in the 2002 bombing of Hamas operative Salah Shehadeh that killed 14 others, including nine children.

Israeli National Infrastructure Minister Binyamin Ben Eliezer, who was defense minister at the time of the attack and was one of seven suspects named in the probe, said the court's decision was "outrageous."

"Terrorist organizations ... use the systems put in place by democratic states to sue a country fighting terrorism," he said.

• Staff writer Robert Marquand contributed from Paris.