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Telephone Surveillance · Call Interception

Call Interception Detection

Detection of active call interception methods including call forwarding exploitation and telecommunications monitoring.

Communications surveillance extends well beyond a bug in a room. Your phone lines — analog, digital, VoIP, and conference call systems — can be tapped, bridged, or intercepted at multiple points along their path. A tap placed at a terminal block in your building's basement, an unauthorized bridge on your PBX, or a conference call that has been joined by an uninvited party are all documented threats that Empire Investigation's telephone surveillance team detects and documents.

Landline tap detection involves impedance testing, loop current analysis, RF detection for active transmitting taps, and physical inspection of terminal blocks, junction boxes, and wiring runs. VoIP and conference line analysis involves network traffic inspection, system log review, and testing for unauthorized concurrent sessions or bridges. Our investigators have the technical and legal knowledge to preserve findings for criminal prosecution or civil litigation.

Methods of Call Interception

Call interception can be accomplished through multiple vectors: exploitation of call forwarding features to reroute calls to a third party, manipulation of carrier-level infrastructure, physical wiretap devices at the network interface, or through software vulnerabilities in smartphone and VoIP platforms. Each method requires a different detection approach.

Indicators of Call Interception

Unlike many surveillance methods, call interception sometimes produces detectable symptoms — unusual call quality, unexpected call drops, bill charges for forwarded calls, or notification messages from carriers. However, sophisticated interception methods produce no observable symptoms. A professional audit is required for definitive verification.

What We Look For

  • Call forwarding exploitation routing calls to unauthorized recipients
  • Carrier-level monitoring exploiting network vulnerabilities
  • Physical interception devices at network interface points
  • VoIP call redirection through compromised SIP infrastructure
  • Unauthorized call recording through compromised endpoints

Our Sweep Process

01

Telephone Account Review

Examination of call forwarding settings and account configurations.

02

Network Interface Inspection

Physical inspection of telephone network access points.

03

Line Characteristic Analysis

Electronic testing of line parameters for anomalies.

04

Carrier Coordination

Guidance on carrier-level verification where appropriate.

05

Documentation

Technical report of all findings and recommended remediation.

Frequently Asked Questions

Confidential Inquiry

Schedule a Confidential TSCM Sweep

If you suspect surveillance or want to verify your environment is secure, professional detection is the only way to know with certainty.

All inquiries handled with complete discretion.