Stocks looked set to begin the new month and quarter with gains on Monday, Oct. 2, even as the death toll rose following a mass shooting in Las Vegas that officials were calling the worst in U.S. history.

Dow Jones Industrial Average futures were up 0.21%, S&P 500 futures added 0.15%, and Nasdaq futures increased 0.21%. 

At least 50 people have 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, according to the Las Vegas Metropolitan Police Department.

The suspect, identified as Stephen Paddock, 64, of Mesquite, Nevada, 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.

Casino stocks fell on Monday morning. MGM Resorts International  (MGM - Get Report)  , parent of Mandalay Bay Hotel and Casino, fell 4%, and Wynn Resorts Ltd. (WYNN - Get Report)  and Las Vegas Sands Corp. (LVS - Get Report) were down more than 1%. Gun stocks surged in premarket trading -- American Outdoor Brands Corp. (AOBC - Get Report) and Sturm Ruger & Co. (RGR - Get Report) both climbed more than 4%.

The S&P 500 and Nasdaq were on track to open above all-time highs on Monday. The two scored 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%.

Tensions between the U.S. and North Korea ratcheted higher over the weekend as President Donald Trump continued his war of words over Twitter. In a series of tweets on Sunday, Trump wrote that Secretary of State Rex Tillerson was "wasting his time trying to negotiate" with North Korean leader Kim Jong-un. He also said that diplomacy with the rogue nation had failed under the Clinton, Bush and Obama administrations. 

Investors were also looking ahead to the September jobs report on Friday, Oct. 6, in what will be the first full month in which the effects of hurricanes Harvey, Irma and Maria on the labor market will be laid bare. Weekly jobless claims have already shown the initial impact with the number of new applications for unemployment benefits seeing an uptick in recent weeks.

Economists surveyed by FactSet anticipate 75,000 jobs to have been added to the U.S. economy in September, a sharp slowdown from the 156,000 jobs added in August. The measure has not fallen below the 100,000 mark since March and has only been below that threshold four times in the past five years.

The unemployment rate is expected to hold at 4.4%. Hourly earnings are forecast to climb by 10 basis points to 2.6% year over year. On a month-by-month basis, earnings are expected to increase to 0.25% from 0.1%.

Updated from 7:44 a.m. ET, Oct. 2. 

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