ATHENS, Greece (AP) — On an early September morning in 1974, a bomb tore apart a TWA Boeing 707 flying near the Greek island of Corfu. All 88 people aboard perished.

Almost exactly 27 years later — September 11, 2001 — the world gaped in disbelief at a new and mind boggling spectacle waged by a new and elusive brethren of terrorists.

The two events are separated by a generation, bookends of terrorism’s ever more bloody evolution.

The mastermind of that first attack, Palestinian terrorist Abu Nidal, 65, was reported dead last Monday, after a murderous career that claimed hundreds of lives. Iraqi Deputy Prime Minister Tareq Aziz said he committed suicide but didn’t provide details. Palestinian officials in the West Bank said his body was found with several bullet wounds in his home in Baghdad.

News reports out of Baghdad said Abu Nidal shot himself in the mouth when secret service agents turned up at his house to take him for interrogation after his presence in Iraq was discovered.

Abu Nidal, whose real name was Sabri al-Banna, entered Iraq “illegally” in 1999 from Iran carrying a fake Yemeni passport, Taher Jalil Habbush, Iraq’s secret services chief, told a press conference.

“He went into a room to change and a shot was fired. The group of agents discovered that he had shot himself in his mouth (with a Smith and Wesson pistol) and the bullet had exited the back of his skull.

“He died eight hours later at the hospital to which he was taken,” Habbush said, without giving the date of his suicide.

Abu Nidal, who had enjoyed Iraq’s patronage in the 1970s and 1980s, had been banned from Iraq in 1983 when Baghdad discovered his involvement in “activities harmful to the security of Iraq and Arab national security,” Habbush said.

The militant rose to infamy in 1974 after he broke with Palestinian leader Yasser Arafat’s Fatah movement and established the Fatah Revolutionary Council in Baghdad to pursue a harder line against Israel.

In its heyday, the group carried out assassinations and hijackings that made Abu Nidal’s name synonymous with global terrorism.

Despite being a sworn enemy of Israel, many of his victims were Arabs, including moderate Palestinian figures who backed negotiations with Israeli left-wingers.

For many, the reports of Abu Nidal’s demise carried an added epitaph: the symbolic passing of the commando-style terrorism that emerged in the Middle East and was ruthlessly waged for decades by Abu Nidal’s Fatah-Revolutionary Council.

In its place has come a menace with greater potential to cause mayhem and foil traditional counter measures. The new threats — led by the al-Qaeda movement founded by Osama bin Laden — are built around loosely linked cells that do not rely on a single leader or state sponsor, experts say.

This important change obscures any clear target for retaliation and limits the chance for the type of internal rivalries that shook Abu Nidal’s faction.

“Abu Nidal’s reported death marks the end for a form of violence that was built on a hierarchy with one clear leader,” said Maria Bossi, an international terrorism analyst based in Athens. “Now we face a network-type of terrorism like al-Qaeda. Because it is not controlled from one source, it is much more dangerous.”

For years, Abu Nidal set a bloody standard in his self-declared war to wipe out Israel. The weapons of choice were small explosives and automatic weapons.

In 1985, Abu Nidal gunmen simultaneously attacked airports in Rome and Vienna, Austria. Eighteen people were killed and 120 wounded.

In the following years, however, bomb attacks linked to other Islamic groups grew progressively larger and the targets more audacious: the first World Trade Centre attack in 1993, the US embassies in Kenya and Tanzania in 1998, the warship USS Cole in Yemen in 2000.

The September 11 attacks thrust terrorism to a once-incomprehensible level.

The next possible step is even more frightening, said experts. Some evidence suggests al-Qaeda was seeking or producing chemical or biological agents. Others fear terrorist engineers could eventually produce a crude nuclear device.

The White House has used such worries in trying to build support for a possible military strike against Iraq — where Abu Nidal took refuge in recent years.

“We must be prepared for new types of attacks: chemical, biological, nuclear. Anything could happen,” said Koichi Oizumi, an international relations professor at Nihon University in Tokyo — where a doomsday cult sprayed sarin nerve gas into the subways in 1995 and claimed 12 lives.

Meanwhile, the Internet and cellular phones allow worldwide mobility and access to information that could prove useful in making weapons.

“This is really the first truly transnational terrorist group,” said Paul Wilkinson, director of the Centre for the Study of Terrorism and Political Violence at St Andrews University in Scotland. “Borderless terrorism is something new and highly dangerous.”

In the past, any group with a known power base would risk annihilation for waging a chemical attack or using another weapon capable of causing mass deaths.

“The price they would have to pay would be too high,” said Umit Ozdag, head of the Eurasian Strategic Research Centre in Ankara, Turkey.

“For example, if Hamas used this against Israel, Israel would retaliate without blinking an eye. … al-Qaeda, on the other hand, is not based in any one particular location,” he said. “It has left Afghanistan and today is all over the world.”

Bruce Hoffman, head of terrorist research for Rand Corp, said al-Qaeda apparently learned from some of the flaws in the rigid Abu Nidal group.

“They saw the need to be much more flexible and maintain a steady supply of money, which is crucial to lubricate the wheels of terrorism,” he said.

“I don’t mean to sound perverse,” he added, “but there is maybe a certain nostalgia for the old style of terrorism where there wasn’t the threat of loss of life on a massive scale … It’s a real commentary on how much the world has changed.”

But some of the lethal power available to terrorist groups can be traced back to the countries now fearing them, said an Israeli terrorism expert, Mordechai Kedar, a professor at Bar-Ilan University.

The formulas for “killing devices” such as chemical and biological agents were first developed by nations before entering the underworld of terrorism, he noted.

“Terror loves the new killing machines,” Kedar said. “As countries industrialised death, so did the terror progress.”