Umarali Kuvatov, an outspoken critic of Tajikistan's autocratic president, was killed by a single shot to the head on a street in Istanbul, where he had been living in exile, according to Turkish media reports.

Kuvatov, 47, a businessman turned government opponent, was head of the Group 24 opposition movement. He had accused Tajik President Emomali Rahmon of corruption and nepotism.

The details of his murder, however, are unclear. Turkey's state-run Anadolu Agency said he was killed by a friend after the two had an argument following dinner. Reuters quotes Radio Ozodi, the Tajik service of Radio Free Europe/Radio Liberty, as saying Turkish police detained a Kuvatov acquaintance in connection with the killing.

However, Turkey's private Dogan news service and the BBC were reporting that the assailant has not been identified and fled the scene after the killing.

According to The Guardian:

"Turkey's Sabah newspaper said Kuvatov and his family had fallen ill after eating dinner with a fellow Tajik, who has since been detained by police. It said Kuvatov had left his house to take his wife and children to hospital."The paper quoted people close to Kuvatov as saying he and his family may have been poisoned before he was shot. It said the assailant was believed to be Tajik and had said a few words before opening fire."

The BBC, quoting an unnamed Tajik opposition representative, says Kuvatov's wife was able to inform relatives of the murder "but she and the two children all later lost consciousness because they were deliberately poisoned, the opposition says."

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