Complex sentence: However, Saleh Al-Arouri's claim of Hamas leadership's involvement was doubted by experts and on 21 August Hamas leader Khaled Mashal claimed Hamas leadership had no prior knowledge of the abductions and murders and had learned about them through the Israeli military.
Split into simpler sentences: However, Saleh Al-Arouri's claim of Hamas leadership's involvement was doubted by experts. On 21 August Hamas leader Khaled Mashal claimed Hamas leadership had no prior knowledge of the abductions and murders and had learned about them through the Israeli military.