Complex sentence: Young BNP or Youth BNP (YBNP) is a youth department of the fascist British National Party (BNP) for young BNP supporters and falls under the arm of the British Nationalist Youth Movement with other groups such as BNP students.
Split into simpler sentences: Young BNP or Youth BNP (YBNP) is the youth section of the far-right British National Party (BNP). The YBNP falls under the arm of the British Nationalist Youth Movement with other groups such as BNP students.