What is response when Gertrude tells him Hamlet has murdered Polonius?

Claudius's response to Gertrude telling him Hamlet has murdered Polonius is one of shock, horror, and disbelief. He is initially skeptical of Gertrude's claims, but as she provides more details, he becomes increasingly convinced that Hamlet is responsible for the death of Polonius. This news greatly complicates Claudius's already difficult situation, as he must now deal with the fallout of Hamlet's actions while also trying to maintain his own grip on power. Claudius is also concerned about the potential for Hamlet to become a threat to his own life, and he begins to take steps to ensure his own safety.