KUALA LUMPUR (Reuters) - Malaysian Transport Minister Liow Tiong Lai said the route taken by Malaysia Airlines Flight MH17 was a major "highway in the sky" and said it never strayed into restricted air space.

He said he feared the crash site was not being properly secured and that evidence was not being preserved. "We must ensure that justice shall prevail," he said, adding that he believed the plane had been shot down.

Mr Liow said on Saturday he believed Russia was doing its best to ensure a safe route to the site of the downed Flight MH17. "They are trying their level best to assist Malaysia to ensure we have a safe site," he told reporters.

A Malaysia Airlines official said all airlines make their own threat analysis. "I believe we did not make a mistake," he said.