fail2ban [Fail2Ban] SSH: banned 221.5.111.162 fail2ban [Fail2Ban] SSH: banned 221.5.111.161 fail2ban [Fail2Ban] SSH: banned 221.5.111.160 Distributed scanning? They were also quite close in time.
fail2ban [Fail2Ban] SSH: banned 221.5.111.162 fail2ban [Fail2Ban] SSH: banned 221.5.111.161 fail2ban [Fail2Ban] SSH: banned 221.5.111.160