In the book, titled “Striking back”, Time magazine's Jerusalem correspondent Aaron Klein confirms suspicions that the Mossad assassinted Wadia Haddad, the leader of the Popular Front for the Liberation of Palestine (PFLP), who was wanted by Israel for his role in several airplane hijackings.

According to Klein, Haddad fled to Baghdad in 1977 after Israel began assassinating Palestinian fighters around the world. The PFLP leader was cautious of his every move, knowing from earlier Israeli tactics that he could be spotted and killed if he walked in the streets or picked up the phone. But the 309-pound food lover had one weakness: chocolate.

At the time, there were no fine chocolates in Baghdad. Mossad spies, working with a Palestinian operative, gave Haddad Belgian chocolates coated in a slow-acting poison that killed him within a few months, Klein said.

Haddad died in March 1978 in a hotel in East Germany, showing symptoms of leukemia but no signs of poisoning.

"Haddad was considered Israel's number one enemy over the hijackings," Klein said. "He wasn't liquidated out of vengeance, even though this motive had existed, but out of the need to neutralize his organization and this desired effect had been achieved," he added.

Klein said that “since the recent publication of his book, none of the information has not been officially denied by the Israel". He also stressed that the Mossad's ability to poison has improved dramatically over the years.

The recent revelation fuels suspicions that Israel poisoned late Palestinian leader Yasser Arafat, who died at the age of 75 of an unknown disease in a French military hospital on November 11 2004. "I can categorically confirm that Abu Ammar (Arafat) was poisoned," exiled Fatah chairman Faruq Qaddumi said at the time.

Arafat’s personal physician, Jordanian Ashraf Al-Kurdi also said "The poison was administered in the food and in the medication he (Arafat) swallowed.”

Klein said there is no concrete evidence that Israel killed Arafat, but noted that it would take several years to prove that poisoning took place because Israel would try to block any investigation.

Israel’s secret intelligence agency assassinated several leaders of Palestinian resistance groups. In October 1996, the Mossad killed the leader of the Islamic Jihad, Fathi Shkaki, in Malta. Israel also killed Hamas‘ spiritual leader Sheikh Ahmed Yassin in March 2004, and his successor Abdel Aziz al-Rantissi the following month.

Despite the success of Israeli assassination operations, there have been several failed attempts in recent years.

The most serious flop occurred in September 1997, when Israeli spies were caught in Jordan after injecting Hamas’ political leader Khaled Meshaal with a poison that would have killed him within 24 hours. The plot was discovered, and Jordan forced Israel to provide an antidote to save Meshaal.

However, the Israeli government vowed to continue its policy of targeted killings. After Hamas' election victory in January, Avi Ditcher, a former head of the Shin Beth security service, even said that Palestinian Prime Minister Ismail Haniya would be "a legitimate assassination target”.