Updated from 5:47 a.m. EDT

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Here are five things you must know for Monday, April 10:

1. -- U.S. stock futures were pointing to a flat to slightly lower start on Monday as geopolitical tensions were making for a nervous Wall Street.

European and Asian stocks traded mixed.

Last week's U.S. missile strikes on a Syrian air base were followed over the weekend by bombings at two Coptic churches in northern Egypt that killed 44 people. Secretary of State Rex Tillerson said the U.S. missile strikes carry a message for any nation operating outside of international norms, including North Korea.

"Volatility was substantially higher last week, and safe-haven asset prices soared as geopolitical tensions and financial uncertainties rose. Therefore, a 'risk-off' sentiment will probably continue to overshadow stock markets in the near term," said Margaret Yang of CMC Markets, the Associated Press reported.

The S&P 500 fell 0.3% last week, the Dow Jones Industrial Average declined 0.03%, and the Nasdaq slid 0.57%.

"The two larger themes at play [in markets] continue to be relatively strong global economic data, along with the timing and extent of Trump administration policy changes," Bill Merz, investment consultant at U.S. Bank's Private Client Reserve, told TheStreet. "A second attempt at getting a health care bill through Congress in the near term is likely to extend the timing of tax reform efforts. This pushes any potential economic impact well into 2018, contributing to the equity market remaining range-bound in recent weeks."

The economic calendar in the U.S. on Monday is quiet with only the Labor Market Conditions Index for March from the Federal Reserve on the docket at 10 a.m. EDT.

(What will move markets this quarter and how should investors position themselves ahead of time? Jim Cramer sat down with four of TheStreet's top columnists recently to get their views. Click here to listen to his latest Trading Strategies roundtable with them and read their advice for stocks, bonds, forex and gold).

2. -- Barclays (BCS) - Get Report  CEO Jes Staley was being probed by the U.K.'s financial watchdogs over an internal investigation into whistleblowing.

Shares of the bank were down slightly in trading in London early Monday.

The Financial Conduct Authority and the Prudential Regulation Authority have started investigations into Staley as to his individual conduct and senior manager responsibilities related to the bank's whistleblowing program and an attempt to try to identify a whistleblower.

Related: Barclays CEO To Be Probed Over Whistleblower Investigation

The Barclays board on Monday said it became aware of the matter in early 2017 when the issue was raised by a concerned employee.

The board brought in an external law firm to conduct an investigation into the matter. The board concluded that Staley had "honestly, but mistakenly" believed he could identify the whistleblower.

The author of the whistleblowing letter hasn't been identified and Staley has apologized for the error, the board said Monday. However, Staley has been formally reprimanded and a "very significant compensation adjustment" will be made to his variable compensation award, the bank said.

3. -- BHP Billiton (BHP) - Get Report  could create $46 billion in additional value for shareholders by spinning off its U.S. oil business, dropping its London listing and increasing capital returns, according to hedge fund Elliott Management.

Shares of the resources giant rose 4.7% in trading in London.

"Despite the first-class quality of most of BHP's assets, BHP as an investment has underperformed," the hedge fund wrote. The underperformance "has been driven by the incomplete status of management streamlining and value optimization of BHP's group structure and asset portfolio."

BHP shares have added 77% over the past year but remain down almost 30% over five years. 

Under Elliott's proposal, BHP's oil business would be carved out and then listed on the New York Stock Exchange, where the hedge fund claims it could be valued at $22 billion, or about $15 billion more than Elliot believes it is worth within BHP.

Elliott also believes BHP should drop its dual-listing and return to its Australian base -- from which Elliott claims about 90% of BHP assets by revenue are managed. That move would enable the company to more quickly monetize about $9.7 billion of tax credits that have accrued in Australia.

BHP didn't immediately respond to Elliot's demands.

4. --  Mondelez International (MDLZ) - Get Report  is preparing to look for a successor to its CEO, Irene Rosenfeld, as the snack giant faces pressure from restive shareholders and the broad shift to healthier eating habits, The Wall Street Journal reported.

The maker of Oreo cookies has hired executive-search firm Heidrick & Struggles, and its board recently discussed outside candidates to potentially replace Rosenfeld, the Journal reported.

The timing of the succession is up to Rosenfeld, who is serves as chairman, and Heidrick & Struggles hasn't yet been asked to interview prospects.

Potential successors among Mondelez's current executives include Tim Cofer, chief growth officer, and Chief Financial Officer Brian Gladden, according to the Journal.

5. -- Spain's Sergio Garcia, 37, held off a late charge by Justin Rose to win the 81 st Masters on Sunday after one playoff hole.

It was Garcia's first major championship, and perhaps he could now shed the unwanted title of "best player to never win a major."

Garcia joins idols Seve Ballesteros and Jose Maria Olazabal, who each won two titles, as a Masters champion.