Violence is also worsening in Israel, where Prime Minister Benjamin Netanyahu has launched a ground offensive in Gaza. His decision came as a surprise, as ceasefire talks between Palestinian officials and Israel appeared to be progressing. Oil prices rose on the news.
To add to the list of worries, just before the market close on Thursday there were reports about an unattended package at the White House. This was subsequently cleared by authorities.
Second-quarter earnings season continued Friday, with General Electric edging higher in early New York trading after the conglomerate reported a profit gain of 13 percent in quarterly net income.
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Late on Thursday, Google reported earnings that missed expectations while revenue topped Wall Street estimates on Thursday.
European airline and insurance stocks fell on Friday due to the crash in Ukraine, and their U.S. equivalents will be worth watching once Wall Street opens.
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