A presidential tweet threatening more tariffs on Chinese imports caused stock markets and oil prices to plunge.

The S&P/TSX composite index closed down 29.52 points at 16,377.04.

In New York, the Dow Jones industrial average was down 280.85 points at 26,583.42. The S&P 500 index was down 26.82 points at 2,953.56, while the Nasdaq composite was down 64.30 points at 8,111.12.

The Canadian dollar traded at an average of US75.66¢, down compared with Wednesday’s average of US76.06¢.

The September crude contract was down US$4.63 at US$53.95 per barrel and the September natural gas contract was down US3.1¢ at US$2.20 per mmBTU.

The December gold contract was down $5.40 at US$1,432.40 an ounce and the September copper contract was down half a cent at US$2.66 a pound.