Official Documents leading to Russian involvement in Afghanistanhttp://www.gwu.edu/~nsarchiv/CWIHP/BULLETINS/b8-9a13.htm
The Soviet Union and Afghanistan, 1978-1989: Documents from the Russian and East German Archives
Excerpted
On December 12, the Politburo met and formally ratified the proposal to intervene. Gromyko chaired the meeting, after having co-signed the proposal together with Ustinov and Andropov. Konstantin Chernenko wrote out, by hand, a short protocol accepting the proposalentitled Concerning the
Situation in Aand had all Politburo members present sign their names diagonally across the text. Kosygin, who almost certainly would have opposed an intervention, was not present. Kirilenko signed after some hesitation. Brezhnev, who entered the room after the brief discussion was
finished, added his name, in quivering handwriting, at the bottom of the page.10
Two days later, the General Staff operative team, headed by Marshal Akhromeyev, was in place in Termez, Uzbekistan (USSR), near the Afghan border. A group from the operational team arrived at Bagram airforce base outside Kabul on December 18.
The main operation started at 3 pm sharp on Christmas Day: airborne troops from the 103rd and 105th air divisions landed in Kabul and in Shindand in western Afghanistan, and units from the 5th and 108th
motorized rifle divisions crossed the border at Kushka and at Termez. Just before nightfall on December 27, Soviet paratroopers, assisted by two KGB special units, attacked Amins residence at Duraleman Palace, and, after overcoming stiff resistance from the Palace Guards, summarily executed the president and several of his closest aides. It waswe were told in Lysebu by the men who devised ita well-organized and successful operation, in which all the strategic objectives were reached on time.
http://www.gwu.edu/~nsarchiv/CWIHP/BULLETINS/b8-9a13.htm
New Evidence on the Soviet Intervention in Afghanistan