One Russian Embassy employee was shot dead in a June 3 attack in Baghdad and four others were kidnapped before being executed by an al-Qaeda linked cell.
President Vladimir Putin gave instructions Wednesday that the secret services should hunt down and kill the perpetrators of the atrocity, and Federal Security Service head Nikolai Patrushev said there would be a substantial reward on offer.
"The National Anti-Terrorism Committee will pay a reward of $10 million for information that leads to a result," said Patrushev, who is also the chairman of the committee.
The UN Security Council strongly condemned the killings Thursday and expressed deep condolences to their families, as well as to the Russian people and government.
The Security Council said no cause could be invoked to justify such terrorist acts against foreign diplomats and it reiterated its resolve to fight terrorism in accordance with its obligations arising from the UN Charter.