In a cellular phone applicable to an information processing apparatus according to the present invention, a CPU of a main control unit executes monitor threads 1 to 3, monitors groups including a plurality of threads set with priority by executing a keep-alive operation to a plurality of monitor threads that monitor operations of threads in the groups, determines whether there is a monitor thread without a response to the keep-alive operation based on responses from the plurality of monitor threads, and terminates delivery of events to the groups with priority higher than the group monitored by the monitor thread without a response to the keep-alive operation if it is determined that there is a monitor thread without a response to the keep-alive operation.