A 32-year-old welder complains of weakness and fever. His illness initially presented as tonsillitis one month earlier. On examination: BT- 38,9°C, RR- 24/min., HR- 100/min., BP- 100/70 mm Hg, hemorrhages on the legs, enlargement of the lymph nodes. CBC shows Hb- 70 g/l, RBC- 2,2 × 1012/l, WBC- 3,0 × 109/l with 32% of blasts, 1% of eosinophils, 3% of bands, 36% of segments, 20% of lymphocytes, and 8% of monocytes, ESR - 47 mm/hour. What is the cause of anemia?