Which respectable government is going to claim responsibility for a supposedly secret assassination? Public killing between nations is usually on a much grander scale and called 'war'. In the wake of the Dubai assassination of a senior member of Hamas, we take a look at other high-profile deaths believed to be the work of secret service agencies.

As a large part of an assassination is its deniability, the killings reported below haven't been claimed ? rather it is common belief that the agencies mentioned were responsible for the following deaths.

Dubai hotel killing

Who: A point man between groups angry at Israel, Mahmoud Abdel Rauf al-Mabhouh was a co-founder of the Al-Qassam Brigades, the military wing of the Islamic resistance movement Hamas. He was rumoured to be the link between the Brigades and the Quds Force, a unit of Iran's military that helps Islamic revolutionaries.

How: Israel's Mossad has been accused of being responsible for his death, first using poison to sedate him before smothering him inside his hotel room.

The international fall-out will continue to damage Mossad's reputation and lose Israel a lot of brownie points it had with friendly nations ? such as Australia ? which took exception to fraudulent copies of civilians' passports being used by agents slipping into Dubai.

Dying in a British hospital

Who: Alexander Litvinenko, a former senior Russian State security service officer (think KGB).

His past: He didn't endear himself to the powers of Mother Russia by accusing his bosses publically of wanting to kill one of Russia's richest men. After being acquitted twice of charges brought against him, he fled to Britain where he authored books in which he accused state authorities of terrorism and assassination.

How: He died in 2006, three weeks after unknowingly swallowing radioactive polonium-210 in his tea. Russia refused Britain's request that Andrey Lugovoy, a Russian politician and former KGB agent that he met the day he fell ill, be extradited to stand trial on charges of murder.

Being hit by Hellfire

Blowing up a family home in the hope of killing a Taliban leader is exactly what the United States government did on 5 August 2009. Baitullah Mehsud was blamed for co-coordinating 80 percent of Taliban suicide attacks in Pakistan from 2007 until 2009. He had a $5-million 'dead or alive' bounty on his head when he died after a CIA-operated drone flew into South Waziristan.

This not-so-secret method of assassination is now common practice as the CIA supports the US in the War on Terror in Pakistan. Officially the CIA started killing people again after President George W. Bush lifted President Gerald Ford's sanction in reaction to the 9/11 attacks.

Some say that despite the collateral damage it's a lot more effective than the secretive assassinations that, as Israel is finding out, are often not so secret.

Speaking truth to power

Who: A 48-year-old mother of two and journalist Anna Politkovskaya.

How: Shot four times in the lift going up to her Moscow flat in 2006.

Why: If the reason why she was killed was publically known, justice may have been served. There is consensus that she died because of doing what she saw as her duty as a Russian journalist and wrote about the crimes committed by the Russians and Chechnians during their continuing cross-border conflict. Before her death, she wrote:, "?if you want to go on working as a journalist, it's total servility to Putin. Otherwise, it can be death, the bullet, poison, or trial - whatever our special services, Putin's guard dogs, see fit."

And during an interview, "I am absolutely sure that risk is [a] usual part of my job; job of [a] Russian journalist, and I cannot stop because it's my duty. I think the duty of doctors is to give health to their patients, the duty of the singer is to sing. The duty of [the] journalist [is] to write what this journalist sees is the reality. It's my one duty."

Despite street protests and a $500 000 reward offered by her newspaper for the names of those who ordered the killing, Vladimir Putin, then Russian Prime Minister kept quiet for three days and then responded with the following: "Politkovskaya's political influence inside the country was of little significance. She was more known in human-rights circles and to the western media. And I think that Politkovskaya's murder caused more harm to the Russian and Chechen authorities than her publications."

Political commentators remarked that investigations into her death would be part of a cover-up as those who killed Politkovskaya walk the same corridors as those who ordered the killing.

A telling quote from General Aharon Yariv, the man who managed the hunting down and killing of the terrorists involved in the Munich Massacre, could summarise how many governments view assassination: "Is it morally acceptable? One can debate that question. Is it politically vital? It was."

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