At one point in the early afternoon in New York, the Nasdaq compositeindex - which reflects the value of tech firms - was down nearly 7% on the day, and had plunged to just half its value from from the high point of 5, 048.6 it reached on 10 March.
An exception was the Shanghai Compositeindex, which ended the day 1.8% higher, largely due to a surge in the value of energy companies, including a 10% jump in China Shenhua Energy Company.