"Two drivers were killed in a head-on collision on the Riga Highway at about 13:00 Moscow time (10.00 GMT). An hour earlier a cargo truck hit four cars in a row on the Minsk Highway, killing five people," the official said.
At approximately the same time, six people, including three children, were seriously injured in an eight-car collision on the Kiev Highway.
"Some of them had to be freed from the car debris by rescue workers," the source said.
Moscow traffic police says all accidents occurred due to speeding in heavy snow and icy road conditions.