WASHINGTON — The body of a top Iranian commander, who was killed in a U.S. drone strike, has arrived in Iran. Throngs of mourners carried the flag-draped casket of Gen. Qassem Soleimani off a plane in Ahvaz in southwestern Iran on Sunday, as President Donald Trump threatened to bomb 52 sites in the Islamic Republic if Tehran retaliates by attacking Americans. 

The tensions take root in Trump pulling out of Iran's nuclear deal with world powers. That accord soon likely will further unravel as Tehran is expected to announce as soon as Sunday another set of atomic limits the country will break. 

The drone strike carried out by the U.S. Friday which killed Iranian General Soleimani further escalated an already tense relationship between Iran and the U.S., into a crisis. The situation has put the Middle East on edge. 

Iran's Information and Telecommunications Minister Mohammad Javad Azari-Jahromi tweeted, "Like ISIS, Like Hitler, Like Genghis! They all hate cultures. Trump is a terrorist in a suit. He will learn history very soon that NOBODY can defeat ‘the Great Iranian Nation & Culture." 

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Oman, the EU and Britain stressed the need for calm and a de-escalation of the crisis as the U.S. and Iran hit back and forth with a war of words over the weekend, Reuters reports.