It is alleged in Dear Mr. President . . .’ The Story of Fifty Years in the White House Mail Room (New York: J. Messner, 1949) by Ira R. T. Smith that in the context of "controversy ... including the Palestine question" in the summer of 1947 someone sent President Truman letter bombs "intended to kill" (see pp. 229-230).
These allegations are repeated in a book by Truman's daughter, Margaret Truman, titled Harry S. Truman (New York: William Morrow & Co., 1973) where they are specifically attributed to Jewish terrorists based in Mandatory Palestine (see pp. 489-490). Margaret Truman's account is unsourced but appears derivative of Smith's.
The allegations, citing Margaret Truman, also appear in an endnote (see n. 11, p. 331) in Political Assassinations by Jews: A Rhetorical Device for Justice by Nachman Ben-Yehuda (Albany: SUNY Pr., 1993).
Are there any records in the Truman Library or elsewhere that address these allegations?