Tehran (dpa) - After days of denial, Iran has now admitted that it was responsible for the crash of a Ukrainian passenger plane with 176 fatalities. The military unintentionally shot the machine down, it was human error, it said. President Hassan Ruhani expressed regret and promised a thorough investigation. The families of the victims are to be compensated. Ruhani also officially apologized to Ukraine for the accidental launch in a phone call with his Ukrainian colleague Volodymyr Selenskyj.