Oct 23 (Reuters) - Wall Street opened sharply lower on Tuesday as disappointing earnings from industrial bellwethers Caterpillar and 3M piled on to concerns over Saudi Arabia's diplomatic isolation, Italy's finances and trade war fears.
The Dow Jones Industrial Average fell 278.95 points, or 1.10 percent, at the open to 25,038.46.
The S&P 500 opened lower by 34.85 points, or 1.26 percent, at 2,721.03. The Nasdaq Composite dropped 140.08 points, or 1.88 percent, to 7,328.55 at the opening bell. (Reporting by Amy Caren Daniel in Bengaluru; Editing by Shounak Dasgupta)