After a rally lasting more than two months, Wall Street hit a stumbling block Thursday as spiking coronavirus cases in several US states helped spur the worst sell-off since March, when market turmoil over COVID-19 was at its peak.

The Dow Jones Industrial Average finished down 6.9 percent, a loss of more than 1,850 points, to 25,128.17, also weighed down by worries over excess valuations and another massive number of US jobless claims.

Bourses in Paris, Frankfurt and London all plunged at least four percent.

"The market got too far ahead of itself," said Markets.com analyst Neil Wilson.

In the US, stocks have followed a fairly unbroken path higher from the market's worst days in March, fueled by optimism over the reopening US economy and the expected boost from aggressive stimulus measures approved in Washington.

But US Federal Reserve Chief Jerome Powell offered a sober outlook on the US economy during a press conference Wednesday after the central bank signaled it planes to keep interest rates low for the next few years in light of the shaky recovery.

Analysts also fixated on increasingly worrisome trends on new coronavirus cases in several states, including Florida, Arizona and Texas.

"Wrong direction," the Houston Health Department in Texas said in a tweet Thursday that showed recent trends in the city. "If we don't take the increasing #COVID19 cases seriously NOW, we may soon end up in a deadly situation.

"Wear a mask, social distance, wash hands & get tested."

LBBW's Karl Haeling said "It's concerning that a lot of states are seeing a spike in rates."

"It's hard to interpret whether that represents a real increase, or just the fact that more states are testing people now," he told AFP.

Heading into this week, analysts had begun describing equity valuations as "frothy" following steady gains since March, saying they do not reflect the grinding recovery many economists anticipate.

"We've been talking about the optimism trade for a while, and it just ran into some facts," JJ Kinahan, chief market strategist at TD Ameritrade, said in a note.

"The facts are we're not fully reopened and businesses aren't all the way back," Kinahan said. "Basically, the market got out a little over its skis."

Losses were broad-based, but some of the worst affected sectors included banks such as Bank of America, down 10.0 percent, oil services companies like Halliburton, down 15.4 percent, and travel-oriented companies including United Airlines, down 16.1 percent and Marriott International, down 10.9 percent.

Boeing dove 16.4 percent, hit by the pullback in the broader market as well as news that 737 MAX contractor Spirit AeroSystems had furloughed staff and halted work on the MAX at Boeing's request. Spirit fell 15.6 percent.

Back in Europe, shares in German airline Lufthansa also dived in Frankfurt by around 10 percent after the company said it would axe 22,000 jobs.

While beaches, bars, cafes and public spaces reopen around the world, there are concerns about a possible second wave of infections in the United States
While beaches, bars, cafes and public spaces reopen around the world, there are concerns about a possible second wave of infections in the United States AFP / CHANDAN KHANNA

New York - Dow: DOWN 6.9 percent at 25,128.17 (close)

New York - S&P 500: DOWN 5.9 percent at 3,002.10 (close)

New York - Nasdaq: DOWN 5.3 percent at 9,492.73 (close)

London - FTSE 100: DOWN 4.0 percent at 6,076.70 (close)

Frankfurt - DAX 30: DOWN 4.5 percent at 11,970.29 (close)

Paris - CAC 40: DOWN 4.7 percent at 4,815.60 (close)

EURO STOXX 50: DOWN 4.5 percent at 3,144.57 (close)

Tokyo - Nikkei 225: DOWN 2.8 percent at 22,472.91 (close)

Hong Kong - Hang Seng: DOWN 2.3 percent at 24,480.15 (close)

Shanghai - Composite: DOWN 0.8 percent at 2,920.90 (close)

West Texas Intermediate: DOWN 8.2 percent at $36.34 per barrel

Brent North Sea crude: DOWN 8.2 percent at $38.55 per barrel

Euro/dollar: DOWN at $1.1292 from $1.1374 at 2100 GMT

Dollar/yen: DOWN at 106.86 yen from 107.12 yen

Pound/dollar: DOWN at $1.2592 from $1.2747

Euro/pound: UP at 89.66 pence from 89.23 pence