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* Industrials hit by fresh round of U.S.-China tariffs
* Commodity prices fall, weighing on energy, material stocks
* All eyes on Powell speech at Jackson Hole on Friday
* Hormel Foods, Sanderson Farms drop as tariffs hit results
* Indexes: Dow down 0.25 pct, S&P and Nasdaq flat (Adds comment, updates to early afternoon)
By Shreyashi Sanyal
Aug 23 (Reuters) - The S&P 500 treaded water on Thursday as gains in technology stocks were offset by declines in commodity-related and trade-sensitive sectors after the U.S.-China trade war escalated with a fresh round of tariffs.
The United States and China imposed tariffs on $16 billion worth of each other's goods, despite ongoing talks. The S&P industrials sector fell 0.34 percent.
Caterpillar fell 1.8 percent and Boeing 0.6 percent, weighing on the Dow Industrials. Technology stocks rose 0.43 percent, helping the S&P and the Nasdaq.
Investors are also assessing the likely political fallout from the legal woes of two former advisers to President Donald Trump, and the outcome of the two-day central bankers' symposium in Jackson Hole, Wyoming.
"The real focus right now is on tariffs taking effect today and I would say that it is a combination of Trump's woes and trade worries that's causing the slight jitters in the markets," said Peter Cardillo, chief market economist at Spartan Capital Securities in New York.
A recent Reuters poll of economists showed U.S. economic growth will slow steadily over the coming quarters due to trade wars.
"I think the theme in Jackson Hole will be the trade war and it's consequences," said Cardillo.
Federal Reserve Chair Jerome Powell's speech at Jackson Hole on Friday will be closely watched for clues on monetary policy, after minutes from the most recent meeting indicated that the central bank could raise interest rates soon.
At 12:44 a.m. EDT the Dow Jones Industrial Average was down 63.65 points, or 0.25 percent, at 25,669.95, the S&P 500 was down 2.37 points, or 0.08 percent, at 2,859.45 and the Nasdaq Composite was up 6.43 points, or 0.08 percent, at 7,895.53.
Only three of the 11 major S&P sectors were higher.
The energy index fell 0.5 percent and the materials index 0.76 percent as prices of crude oil and metals declined due to trade war worries, while the dollar strengthened on expectations of rate hikes.
U.S. meat producers Hormel Foods and Sanderson Farms said higher Chinese tariffs have led to domestic oversupply, forcing price cuts and hurting their quarterly results. Their shares fell about 3 percent.
Victoria's Secret-owner L Brands dropped 11.2 percent after cutting its full-year profit forecast.
Data showed jobless claims fell last week, a sign the labor market was holding firm despite trade tensions.
Declining issues outnumbered advancers for a 1.77-to-1 ratio on the NYSE and a 1.30-to-1 ratio on the Nasdaq. The S&P index recorded 21 new 52-week highs and one new low, while the Nasdaq recorded 119 new highs and 18 new lows. (Reporting by Shreyashi Sanyal in Bengaluru Editing by Saumyadeb Chakrabarty)