US equity indexes fell Thursday as mounting credit concerns at two regional banks helped push government bond yields lower, while the Russia-Ukraine war looked set to return to center stage.

The Nasdaq Composite fell 0.5% to 22,562.537, with the S&P 500 down 0.6% to 6,629.07 and the Dow Jones Industrial Average 0.7% lower at 45,952.24. Financials led the decliners intraday, while technology was the sole gainer.

Shares of Zions Bancorporation (ZION) slumped 13% after the lender disclosed a $50 million charge-off to be reflected in Q3 earnings. The charge stems from an internal review of two borrowers and their obligators, which uncovered "apparent misrepresentations and contractual defaults," along with other irregularities involving the loan and its collateral, Zions said Thursday in a regulatory filing.

Meanwhile, Western Alliance Bancorp's (WAL) shares dropped 11% after the company initiated a lawsuit against Cantor Group V in August for alleged fraud related to a note finance revolving credit facility.

"When you see one cockroach, there are probably more," JPMorgan CEO Jamie Dimon said on the bank's earnings conference call earlier this week, related to the collapse of First Brands and Tricolor Holdings.

The SPDR S&P Regional Banking ETF (KRE) slumped 6.2% intraday.

The CBOE Volatility Index, also known as a fear gauge, soared almost 23% to 25.31, its highest since April.

US Treasury yields fell, with the two-year yield down 8.2 basis points to 3.42% and the 10-year rate 6.9 basis points lower at 3.98%.

President Donald Trump said "great progress" was made during a phone call with his Russian counterpart, Vladimir Putin, on Thursday, with the pair agreeing to face-to-face talks in Hungary, the BBC reported. He said the call, the first with Putin since mid-August, was "very productive", adding that teams from Washington and Moscow will meet next week.

The BBC also reported India's foreign ministry is "not aware" of a call in which Trump claimed Prime Minister Narendra Modi agreed to stop purchasing Russian oil. On Wednesday, Trump said his Indian counterpart had "assured me today" that it would end Russian oil imports, a move the US has pushed for in a bid to mount economic pressure on the Kremlin to end the Ukraine war.

Meanwhile, US Treasury Secretary Scott Bessent said the ongoing government shutdown, which began on Oct. 1, could cost the US economy up to $15 billion per week, equivalent to a hit to gross domestic product of about 0.2 percentage points, according to media reports.

Gold futures were up 3.1% to $4,331.91 after touching yet another all-time high, and silver futures traded 3.8% higher at $53.35 after hitting a new peak earlier in the session.