April 10 (Reuters) - Wall Street's main indexes extended

declines in afternoon trading on Thursday, with the benchmark

S&P 500 plunging more than 5% as investor concerns about the

economic damage from U.S. tariff policies returned to the fore.

Stocks shot higher on Wednesday after U.S. President Donald

Trump declared a 90-day tariff pause for many countries but

raised the levy on imports from China to 125%.

The pause on tariffs from dozens of trading partners came

less than 24 hours after they kicked in.

At 12:17 p.m. ET, the Dow Jones Industrial Average

fell 1,799.95 points, or 4.43%, to 38,808.24, the S&P 500

lost 285.64 points, or 5.25%, to 5,170.61 and the Nasdaq

Composite lost 1,045.35 points, or 6.10%, to 16,079.62.