MOSCOW, May 3 (RIA Novosti) - A Soyuz-U rocket carrying a Kosmos-class military satellite has lifted off from the Plesetsk space center in the north of Russia.

"The launch took place in the interests of the Defense Ministry," a space agency source said, adding that a Space Force military unit carried out the launch.

The Kosmos satellite will join a military orbital grouping.

Soyuz rockets are used to put a number of different-type crafts into orbit, including the Progress freighters currently servicing the International Space Station.