Complex sentence: From 1949 to 1951 the head of intelligence in Committee of Information was (Sergey I.S), in 1951 he was replace by (Jewgienij Pitowranow), long time secret service worker.
Split into simpler sentences: From 1949 to 1951 the head of intelligence in Committee of Information was (Sergey I.S). In 1951 he was replace by (Jewgienij Pitowranow), long time secret service worker.