Officials with FireEye said on Tuesday the hackers appear to belong to a group it refers to as APT33 DUBAI: A cybersecurity firm is warning that Iranian government-aligned hackers have stepped up their efforts in the wake of President Donald Trump pulling America from the nuclear deal. Officials with FireEye said on Tuesday the hackers appear to belong to a group it refers to as APT33, an acronym for “advanced persistent threat.” APT33 used phishing email attacks with fake job opportunities to hack computers. FireEye says the “cyberespionage” effort from July 2 through July 29 targeted primarily Mideast energy firms, as well as some organization in North America and Japan. Iran’s mission to the United Nations didn’t immediately respond to a request for comment. FireEye similarly issued a warning about APT33 a year ago. It says “the current geopolitical climate” may lead to more hacking attempts by the group.