(Bloomberg) -- Wall Street hopes that the Federal Reserve might be able to ease up on its battle against inflation later this year were decisively dashed Thursday when consumer price index data for September came in unexpectedly hot. Core CPI, which excludes food and energy, increased 6.6% from a year ago, the highest level since 1982.

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Stock futures on the S&P 500 sank below 2% after rising as much as 1.3%, and 10-year Treasury yields jumped above 4%.

“Horrible CPI number,” said Andrew Brenner, the head of international fixed-income at NatAlliance Securities. He wondered what the Fed might have to do on interest rates: “Will they go 100 basis?”

Here’s what other analysts were saying:

Seema Shah, Chief Global Strategist, Principal Asset Management:

“There can’t be anyone left in the market who believes the Fed can raise rates by anything less than 75bps at the November meeting. In fact, if this kind of upside surprise is repeated next month, we could be facing a fifth consecutive 0.75% hike in December with policy rates blowing through the Fed’s peak rate forecast before this year is over.”

“The composition of the inflation reading is perhaps even more worrisome than the overall number. Increases in shelter and medical care indices, the stickiest segments of the CPI basket, confirm that price pressures are extremely stubborn and will not go down without a Fed fight.”

Steve Chiavarone, senior portfolio manager at Federated Hermes:

“This report raises the risk that we may see a new cycle high in headline inflation before the end of the year. With energy prices moving back up, a mid-90s oil price in December could see us surpass the 9.1% headline peak from June.”