Dow rockets 600 points as optimism grows around economic reopenings

• US stocks spiked roughly 2% on Tuesday as investors' optimism about economic reopenings overshadowed US-China tensions.
• Travel and leisure stocks including United Airlines, Carnival, and MGM Resorts soared as states continued to relax lockdown measures.
• The White House said on Sunday that it would likely sanction China if the country implemented a controversial national-security law in Hong Kong, further escalating stresses between the economic giants.
• West Texas Intermediate crude oil bounced as much as 3.9%, to $34.54 per barrel.
• Watch major indexes update live here.

US stocks leaped on Tuesday as investors mulled economic reopenings and new US-China tensions.

States continued to relax lockdown measures through Memorial Day weekend, ushering in a new test for markets battered by the coronavirus pandemic. Some of the biggest gainers in early trading included firms that were hit hardest by the outbreak, with United Airlines, Carnival, and MGM Resorts all gaining at least 8%.

New pressure between Hong Kong and China dampened sentiment and threatened to escalate US-China tensions. The White House said on Sunday that the US would likely sanction China if it enacted a controversial national-security law in Hong Kong.

Here's where US indexes stood soon after the 9:30 a.m. ET open on Tuesday:

• S&P 500: 3,016.31, up 2.1%
• Dow Jones industrial average: 25,054.29, up 2.4% (589 points)
• Nasdaq composite: 9,472.94, up 1.6%

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The rally placed the S&P 500 above 3,000 for the first time since early March.

Investors also looked to news from the biotech firm Novavax's efforts to create a coronavirus vaccine. The company announced on Monday that it had begun human trials of its vaccine candidate and expected results in July. The company's shares jumped as much as 16% in early trading.

Markets have previously soared on announcements of positive study results, most recently surging after Moderna reported positive developments in trials of its experimental vaccine.

West Texas Intermediate crude oil climbed higher through the session, leaping as much as 3.9%, to $34.54 per barrel. Brent crude, the commodity's international standard, gained 3.8%, to $36.48.

The positive start followed the market's best week since early April. Despite a mixed close in Friday trading, major US indexes surged through last week on Moderna's announcement and growing optimism about economic reopenings. Inflows to major tech stocks like Facebook and Apple also lifted the highly concentrated benchmarks.

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