Stock trading was briefly halted Monday for the first time since 1997 after a tumultuous selloff triggered an automatic curb on trading.

Just minutes after the stock market opened, the S&P 500 fell 7% from its previous close—triggering a circuit breaker that halted trading across the entire stock market for 15 minutes. When trading resumed at 9:49 a.m. ET, major indexes managed to come off their lows and hold above them for the rest of the morning.

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