Internal Security Operations (ISO) are a critical yet often contentious component of counter-insurgency efforts, which directly impact local governance and public trust. This study assessed the Internal Security Operations of the 404th Regional Mobile Force Battalion 4A (RMFB4A) operating in the insurgency-affected areas of Rizal Province, Philippines. It focused on determining the unit's capability and effectiveness across four key operational domains: police-community relations, execution of warrants, intelligence operations, and counter-terrorism, and how these operations contribute to peace and order, public safety, economic stability, and community engagement. An explanatory-sequential mixed-methods design was employed, gathering quantitative data on operational capability and effectiveness from ISO personnel, supervisors, and community members, and followed by qualitative insights from interviews and focus group discussions to explore their challenges. The findings revealed a consistent pattern where ISO personnel and ISO supervisors rated their operational performance as highly capable and effective, while community members expressed more reserved assessments, highlighting a perception gap that warrants attention. Statistical analyses confirmed significant differences in ratings across all respondent groups and variables. Qualitative findings identified operational barriers such logistics limitations, persistent trust deficit, PNP and LGU partnership, environmental and logistical barriers, and communication, coordination and joint operations. To address these challenges, an intervention titled BRIDGE is proposed aimed at improving tactical readiness, fostering stronger police-community partnerships, and enhancing overall mission effectiveness. Generally, the study advocates for a more inclusive and community-driven approach to internal security that aligns operational strategies with developmental goals for lasting peace and stability in insurgency-affected areas.