-International benchmark Brent crude surged toward $70 a barrel during early morning trading, before paring gains to trade around $68.73.

-U.S. West Texas Intermediate gained $2.19, or 3.6%, to trade at $63.37. Earlier in the session it hit its highest level since April.

-General Qasem Soleimani, who led a special forces unit of Iran's elite Revolutionary Guards, was killed in a U.S. airstrike in Baghdad, the Pentagon confirmed on Thursday night.

Oil prices surged 4% on Friday following confirmation by the Pentagon that Iran's top commander was killed in a U.S. airstrike in Baghdad, raising concerns of a bigger conflict between the two countries that could disrupt energy production in the region.

The U.S. military took the "decisive defensive action to protect U.S. personnel abroad by killing Qasem Soleimani," a statement by the U.S. Department of Defense said Thursday night. It was a directive from the U.S. president, the DOD said.

International benchmark Brent crude surged 3.7%, or $2.48, to $68.73 after trading as high as $69.50 at one point. U.S. West Texas Intermediate gained 3.6%, or $2.19, to trade at $63.37, its highest level since May. Earlier in the session WTI reached $64.09, its highest level since April.

The attack will likely "provoke significant retaliation" from Iran as well as Iranian-backed militia in Iraq, said Matthew Bey senior global analyst at Stratfor.

Iran is likely to return to backing attacks on oil infrastructure in the Persian Gulf and the rest of the Middle East, Bey told CNBC. Tehran could also consider attacks on Saudi Arabia's oil infrastructure if tensions escalate, and it would have both the "capability" and "willingness" to attack major choke points that would "take months to rebuild" in Saudi Arabia, he said.

Soleimani, who led a special forces unit of Iran's elite Revolutionary Guards, was killed, along with Abu Mahdi al-Muhandis, the deputy commander of Iran-backed militias known as the Popular Mobilization Forces, Iraqi television and officials initially reported. He is a key figure in Iranian politics and has been blamed by the U.S. for this week's attack of the U.S. embassy in Baghdad.