TRUMAN SAYS RUSS HAVE A-BOMB

Washington, Sept. 23 (AP)-An atomic explosion has occurred in Russia--a fateful portent that the Soviets have broken an American A-bomb monopoly on which the non-Communists world depended so heavily.

      The historic news, comparable only in significance to the announcement of the Hiroshima blast of Aug. 6, 1945, was given to the world today by President Truman in these words:

      "We have evidence that within recent weeks an atomic explosion occurred in the U.S.S.R."

      He did not say it was an atom bomb that exploded somewhere in the vast reaches behind the Iron Curtain. But Secretary of State Acheson said he assumed the blast was that of an atomic weapon--and there was every indication that the United States is no longer the sole possessor of the dread secret.

'Eventual Development Expected'

      As a matter of fact, a high U.S. official told a reporter tonight:

      "There's no question about it. It was an atomic bomb. But so far as we know Russia has made only one bomb. They'll never catch up with us."

      Does it mean World War III? High U.S. policy makers were of the view that it does not bring war any closer. For one thing they pointed out that the United States has a four-year head start in atomic bomb manufacture. They figured that the Soviets would be wary of starting an atomic struggle in which retaliation could be so swift.

      Commenting on the news, Gen. Bradley, chairman of the Joint Chiefs of Staff, said:

      "The calmer the American people take this the better."

      "We have anticipated it for four years and it calls for no change in our basic defense plan."

      Bradley himself spent part of the day playing golf.

      The formal statement from the White House was couched in calm tones.

      "Ever since atomic energy was first released by man, the eventual development of this new force by other nations was to be expected," the President said. "This probability has always been taken into account by us. . . .

Terrific Impact

      Mr. Truman's disclosure, though long anticipated, hit with a terrific impact in world capitals. Major international repercussions with possibly a sharp change in the atmosphere of the East-West "cold war," were seen as inevitable.

      On Capitol Hill, Sen. McMahon (D) Ct., chairman of the Senate-House Atomic Energy Committee, and several other members of Congress suggested anew that the vital hour has arrived for President Truman to meet with Premier Stalin.

      McMahon suggested that Mr. Truman might even go to Moscow for such a meeting if that is the only place it could be held. The President has repeatedly offered to confer with Stalin in Washington, but has said he would not again go overseas to meet the Soviet leader.

May Be in Infancy

      Although military experts in general believe that Russia at last has learned how to make the atomic bomb, they suggested that Soviet development of the weapon may still be only in its infancy. One said the Russians are probably in the "Los Alamos state"--an allusion to the New Mexico proving grounds where the first U.S. atomic bomb test was held on July 16, 1945.

      Three weeks after the Los Alamos test the first A-bomb ever used in warfare was dropped on Hiroshima, Japan.

      While State Department officials say they do not believe the danger of war is either increased or decreased some Congress members said the threat to peace has been magnified. . . .

      Sen. Flanders (R), Vt., quickly offered a resolution that the United States enter into negotiations with Russia pledging that neither country would use the atomic bomb unless attacked by others.

      In both chambers, Republicans sharply criticized Mr. Truman for "withholding" the announcement until after the Senate had passed that administration's $1,314,010,000 global arms aid bill. The measure passed the Senate last night.

      Rep. Keating (R), N.Y., called the President's action "shocking," but McMahon said Mr. Truman had to be "sure of the definiteness of his information" before he would make any announcement.