In October 97 these tensions came to a head when the Praetorian Guard , led by Casperius Aelianus , laid siege to the Imperial Palace and took Nerva hostage . He was forced to submit to their demands , agreeing to hand over those responsible for Domitian 's death and even giving a speech thanking the rebellious Praetorians . Titus Petronius Secundus and Parthenius , Domitian 's former chamberlain , were sought out and killed . Nerva was unharmed in this assault , but his authority was damaged beyond repair .