U.S. stocks closed mixed Friday. Investors piled into the safety of the dollar and government bonds after fresh Covid-19 restrictions in Europe clouded prospects for the global economic recovery.

The tech-heavy $Nasdaq Composite Index(.IXIC.US)$ climbed 0.4%, or 63.73 points, to 16057.44, its 46th record this year.

The $S&P 500 index(.SPX.US)$ slipped 0.1%, or 6.58 points, to 4697.96 after closing at an all-time high Thursday. The $Dow Jones Industrial Average(.DJI.US)$ declined 0.7%, or 268.97 points, to 35601.98, its second consecutive weekly decline.

Covid-19 cases are rising in the U.S. and Europe, according to data from Johns Hopkins University. The Austrian chancellor announced Friday that his country would go into a nationwide lockdown starting Monday, with restaurants and retail sectors to close. Areas in Germany are also going into a partial lockdown next week.

"As Covid spreads in Europe and restrictions are strengthened in places in Germany and Austria, there's a general recognition that things may not be going the right way," said Sebastien Galy, a macro strategist at Nordea Asset Management. "This affects sentiment, both within markets and in households."

Stock valuations are at extremes, he added: "We had a relief rally from earnings, but now people are concerned about what comes next."

Oil prices fell, hammered by concerns about the effect of renewed lockdowns on energy demand. Brent crude, the global oil benchmark, declined 2.9% to $78.89, its fourth consecutive weekly decline.

"Today we are seeing a very typical end of week sell-off as traders decide it's not worth the risk to await more potential demand-side bearish news," research company Rystad Energy said in a statement.

Philip Orlando, chief equity market strategist at Federated Hermes Inc., said he expects oil prices to rise toward the end of the year, thanks to inflation, surging demand and diminishing supply.

The yield on the benchmark 10-year Treasury note dropped to 1.535% Friday from 1.586% Thursday. Bond prices rise when yields decline.

Safe-haven currencies strengthened, with the WSJ Dollar Index rising.

Investors seem to be adjusting their positions ahead of Thanksgiving week, potentially leading to exaggerated moves, said Christopher Brown, co-portfolio manager of the total return bond strategy at T. Rowe Price Group Inc. Investors, he said, will likely soon go back to paying more attention to inflation.

"I suspect Covid has sort of faded into the background," Mr. Brown said. "I think we're going to have wobbles like this. Is it ever going to go away? Probably not."

$Foot Locker(FL.US)$ declined 12%, or $6.88, to $50.68 after the retailer said it expects supply-chain issues to persist. $Farfetch(FTCH.US)$ sank 14%, or $6.33, to $39.26 after the fashion e-commerce company reported revenue that missed Wall Street's estimates. Financial software firm $Intuit(INTU.US)$ climbed 10%, or $63.40, to $692.34 after it raised its full-year guidance.

Shopping-mall and travel stocks were among the worst performers in the Stoxx Europe 600. U.S.-listed travel companies also took a hit. $Airbnb(ABNB.US)$ declined 3.9%, or $7.91, to $196.42, and cruise operator $Carnival(CCL.US)$ fell 2.2%, or 46 cents, to $20.49.

In Asia, major benchmarks were mixed. The Shanghai Composite Index rose 1.1% and Japan's Nikkei 225 added 0.5%. Hong Kong's Hang Seng Index declined 1.1%. It was weighed down by e-commerce giant Alibaba, which cut its growth forecast this week.