A hybrid circuit interrupter can be used for medium voltage direct current applications, among other applications. The circuit breaker includes a vacuum circuit interrupter and an electronic power interrupter that are electrically connected in parallel. The vacuum circuit interrupter is normally closed and the electronic power interrupter is normally off, so that current passes through the vacuum circuit interrupter in a non-interrupt mode. When an interrupt condition is detected, the electronic interrupter will turn on, and current will pass through the electronic interrupter as the vacuum interrupter is opened. A current injector may draw current from the vacuum interrupter to the electronic power interrupter. An isolation switch may maintain the system in a non-conducting state when interruption is complete.