The World - News from Sept. 8, 1986

The Soviet Union said the United States conducted a secret nuclear test last Thursday in the Nevada desert--the fourth such explosion that the Kremlin has alleged since it imposed a moratorium on testing 13 months ago. Quoting what it called a U.S. anti-war group, the official news agency Tass said the latest test caused a tremor measuring 3.5 on the Richter scale and probably involved a yield of less than 20 kilotons. The Defense Department declined to comment on the report. Since the moratorium, the United States has acknowledged conducting 15 nuclear tests; the Soviets contend there have actually been 19.