Complex sentence: Concerned for his safety, Amin moved from the Presidential Palace, in the centre of Kabul, to the Tajbeg Palace, which had previously been the headquarters of the Central Army Corps of the Afghan military.
Split into simpler sentences: Concerned for his safety, Amin moved the Presidential Palace in the centre of Kabul to the Tajbeg Palace. The Tajbbeg Palace had previously functioned as the headquarter of the Central Army Corps of the Afghan military.