The Dubai killing of the Palestinian militant Mahmoud al-Mabhouh could be straight out of a spy thriller. The hit squad -- which, it emerged today , was travelling under the identities of real British citizens, and with false passports -- underwent physical transformations with wigs, beards and hats.
The assassins employed counter-espionage tactics such as travelling in separate taxis, using only cash and changing mobile phone frequently. And they trailed their target so closely that he actually had to steer his luggage trolley past one of his assailants within moments of arriving in Dubai.
It has been alleged that Israel played a part in the killing. State-sponsored assassinations are couched in secrecy, unless they explode into the press in this way. What was the diplomatic fallout from some of the other meticulously executed murders that have made it into the public domain?
1. Alexander Litvinenko
The former KGB officer and Russian Federal Security Bureau agent was living in the UK after gaining political asylum. But on 1 November 2006, he suddenly became ill and was admitted to hospital. He died three weeks later of acute radiation syndrome, after drinking a cup of tea poisoned with polonium-210. It was the first recorded case of anyone having this lethal nuclear isotope in their body.
Litvinenko had previously written two books critical of Vladimir Putin, and also wrote an article  in the Daily Mail from his deathbed, accusing the then president of being responsible for the poisoning. Investigations into the affair damaged diplomatic relations between Britain and Russia. In July 2008, a British secret service source told BBC2's Newsnight: "We very strongly believe the Litvinenko case to have had some state involvement."
2. Rafiq Hariri
The former Lebanese prime minister was killed on 14 February 2005 when the equivalent of about 1,000kg of TNT exploded as his motorcade drove past the St George Hotel in Beirut. The investigation into his death is still ongoing, but its initial reports suggested that the Syrian government could be linked to the assassination. Syria was occupying Lebanon at the time, and had extensive intelligence networks in the country. Hariri had adopted an anti-Syrian stance after resigning from office in 2004.
A UN report found evidence that both Damascus and Lebanese officials were involved. In 2005 Abdul Halim Khaddam, a former Syrian vice-president, suggested on television that President Bashar al-Assad was involved, prompting Syrian MPs to demand treason charges. The mandate for the investigation has been repeatedly extended.
3. Zoran Đinđić
The Serbian prime minister was assassinated in March 2003 after efforts to rid his country of organised crime. The targeted crime groups had close ties to parts of the Serbian secret police, many of which were still loyal to the deposed leader Slobodan Milosevic.
At the command of Milorad Ulemek, a former commander for the Yugoslavian secret police and leading player in a top organised crime gang, a soldier, Zvezdan Jovanović, shot Đinđić from a building opposite the main government headquarters in Belgrade. The single bullet went straight to the heart, and he died nearly instantly.
Ulemek -- who had spent four years prior to the assassination travelling on a false passport stolen from the Croatian embassy -- was later convicted. Of the 12 men convicted of the crime, five are still on the run.
4. Operation Wrath of God
And finally, one that has been the topic of several films. Over a period of up to 20 years, units under the control of Mossad assassinated individuals alleged to have been involved in the 1972 Munich massacre of Israeli athletes.
With the authorisation of Prime Minister Golda Meir, secretive squads killed dozens of people suspected of involvement, in countries across Europe. This led to the mistaken murder of an innocent man in Lillehammer, Norway, in 1973.
Information about the way the crimes were organised is limited: given the covert nature of the operation, we must rely on just a few sources. Those assassinated include Mahmoud Hamshari, killed by an exploding telephone in 1972, and Hussen al-Bashir, killed in 1973 when a bomb hidden under his bed in a hotel in Cyprus was remotely detonated.
Mossad agents involved in the 1979 killing in Beirut of the Black September leader, Ali Hassan Salameh, had travelled on British and Canadian passports.