News In Brief

More countres join USSR in boycott of Olympics

Afghanistan dropped out of the Los Angeles Olympics Sunday, bringing to eight the number of countries boycotting the Olympics. Czechoslovakia and Laos pulled out Saturday; Mongolia and Vietnam on Friday. East Germany and Bulgaria had previously joined the Soviet Union in a decision to stay away from the games, scheduled to begin July 28.

The lack of automatic approval from Moscow's allies for the Soviet decision to stay away from the games indicated a strong element of dissent, Western diplomatic sources said. The diplomats said the Soviet Union apparently announced its decision not to attend the Los Angeles games without consulting its allies.

The Soviet news media has said the decision was based on a failure to ''guarantee'' the security of Soviet athletes, the heavy commercialization of the games, and concern about ''anti-Soviet hysteria'' in the United States.