(a) If at any time during the period of probation there shall be reasonable cause to believe that the probationer has violated any of the conditions of his or her probation, the probation officer may arrest him or her with or without an order or warrant, or the court which placed him or her on probation, or the judge thereof in vacation, may issue an order for his or her arrest, whereupon he or she shall be brought before the court, or the judge thereof in vacation, for a prompt and summary hearing.