Anna Duritskaya, only known witness to Nemtsov's murder, flies to Kyiv

The Ukrainian model who was with Russian opposition leader Boris Nemtsov when he was shot has returned to Kyiv.

Anna Duritskaya flew into the Ukrainian capital and was swiftly whisked away in a car with blacked-out windows.

Her lawyer, Vadim Prokhorov, said she had been questioned extensively by authorities.

“Anna Duritskaya has fully-cooperated with Russian investigators, I can state that as her lawyer. Three days were spent cooperating with Russia’s Investigative Committee. She has given a full and exhaustive account of her last hours with Boris.”

In an interview with a Russian TV channel Duritskaya said she had not seen Nemtsov’s attacker.

“I only saw a light-coloured car,” she said, “but I didn’t see the model or the number plate of the car that was driving away.”

Questions have been raised about how the shooting could have taken place so close to the Presidential palace, which is considered one of the most secure areas of the capital.

Dozens of security cameras monitor the streets around the Kremlin, but none captured the moment Nemtsov was gunned down.

A local television station broadcast this low-resolution footage from one of its web cameras that it said showed the couple shortly before Nemtsov was killed.

His murderer remains at large, while the murder weapon and car that was seen driving away have yet to be tracked down.