Here are five things you must know for Monday, Oct. 2:

1. -- Las Vegas police said at least 50 people died and more than 200 others were injured after a gunman opened fire on a music festival from the 32nd floor of the Mandalay Bay Hotel and Casino late Sunday, Oct. 1. 

The Las Vegas Metropolitan Police Department had said earlier that the suspected shooter had been taken down and didn't believe any others were involved. However, Sheriff Joseph Lombardo later said the shooter's suspected companion, named as Marilou Danley, was still at large in the city.

The suspect was identified as Stephen Paddock, 64, of Mesquite, Nevada, according to NBC News. The suspect was killed by officers at the scene after allegedly targeting concertgoers at the Route 91 Harvest Festival on the Las Vegas Strip during a performance by country-and-western artist Jason Aldean just after 10 p.m. local time.

A Nevada sheriff said one on-duty officer was in critical condition and another was wounded, the Associated Press reported.

Lombardo said two off-duty officers died.

2. -- U.S. stock futures rose on Monday, Oct. 2, as the benchmark indexes looked to extend their record runs as the fourth quarter kicks off.
The S&P 500 and Nasdaq reached new records on Friday, Sept. 29, with the S&P 500 closing at an all-time high for the second day in a row. 

Stocks also closed out both September and the third quarter with gains. The S&P 500 rose 1.9%, its sixth straight month of gains. The Dow increased nearly 2% and the Nasdaq roughly 1%. During the third quarter, the S&P 500 has climbed more than 3%, the Dow 4.8%, and the Nasdaq 5.7%.

For Monday, the  economic calendar in the U.S. includes the PMI Manufacturing Index for September at 9:45 a.m. ET, the ISM Manufacturing Index for September at 10 a.m., and Construction Spending for August at 10 a.m.
Earnings are expected Monday from Cal-Maine Foods Inc. ( CALM - Get Report) .
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3. -- Facebook Inc. ( FB - Get Report) plans to provide Congress with more than 3,000 ads that ran around the time of the 2016 presidential election and are linked to a Russian ad agency.

Company officials will meet with the House and Senate intelligence committees and the Senate Judiciary Committee on Monday to hand over the ads, a Facebook official told the Associated Press.

Reports emerged in September that attempts were made by Russian operatives to use Facebook to spread misinformation and divisive political rhetoric. The social media company said it found 450 accounts and about $100,000 was spent on the ads.

Twitter Inc. (TWTR - Get Report) has said it found postings linked to those same accounts, and the House and Senate intelligence panels have asked both companies, along with Alphabet Inc.'s (GOOGL - Get Report) Google, to testify publicly in the coming weeks.

None of the companies have said whether they will accept the invitations, the Associated Press noted.

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4. -- Subscribers to Altice USA Inc.'s ( ATUS - Get Report)  Optimum cable TV service avoided a blackout of Walt Disney Co. ( DIS - Get Report) channels on Sunday as the two companies said they were close enough to signing a new programming agreement to extend a contract hours before it was due to expire. 

"We have reached an agreement in principle and have extended the deadline accordingly to try and finalize the terms," Altice said in an e-mailed statement. 

Disney had warned that it might withdraw its channels from Optimum cable-TV service if talks reached an impasse. A blackout would have affected about 3.1 million subscribers in the New York metropolitan area.

Altice USA was created following its French owners' acquisition last year of Cablevision Systems Corp. and Suddenlink Communications Inc., though the contract talks only affected former Cablevision subscribers. Altice's total footprint reaches 4.9 million subscribers in 21 states.

5. -- U.K. airline stocks surged Monday after discount carrier Monarch Airlines PLC effectively filed for bankruptcy protection late Sunday.

Low-cost airline Easyjet PLC  (ESYJY  jumped 3.5% and budget carrier Ryanair PLC  (RYAAY - Get Report)  rose 2.5% on Monday. The owner of British Airways, International Consolidated Airlines Group (ICAGY  , gained 1.5%.

Monarch, the low-cost airline and packaged tour operator fell into administration because of mounting costs and the increasing competitive nature of low-cost air travel, making it the biggest U.K. airline to cease trading.

All flights have been grounded, leaving 110,000 passengers stranded abroad. The administrators and the Civil Aviation Authority were working to repatriate the passengers over the next two weeks.

Updated from 6:01 a.m. ET.

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