On February 3, 2024, Lithuanian Armed Forces reported the discovery of a Russian hydroacoustic sonar used for submarine detection on the Curonian Spit.

Intelligence & EspionageSignals/Technical Intelligence (SIGINT/TECHINT)Electronic surveillance

Aggressor

Summary

On February 3, 2024, Lithuanian Navy received a report from a civilian about finding an unusual device with Russian inscriptions on the Curonian Spit. Military experts identified it as a Russian-made hydroacoustic sonar used for intelligence gathering and locating submarines. The device was not operational and is currently stored with the Lithuanian Navy. Lithuanian Armed Forces noted this sonar uses hydroacoustic sensors to detect and track large underwater objects nearby. Similar Russian sonar devices were found in 2021 near Lithuania in the Baltic Sea and near the southern coasts of the United Kingdom and Ireland in the Atlantic Ocean.

Classification

Confidence: High

The event involves discovery of a Russian hydroacoustic intelligence device dedicated to submarine detection found on Lithuanian territory, clearly indicating hostile espionage activity consistent with Russian hybrid warfare methods.

Source URL

https://rus.delfi.lv/57862/abroad/56324468/foto-na-kurshskoy-kose-nayden-rossiyskiy-razvedyvatelnyy-sonar

Open source

Provenance

Publisher: csv-import
Submitted: Feb 14, 2026, 12:22 UTC
Last updated: Nov 8, 2026, 20:13 UTC
Event time: Feb 3, 2024, 00:00 UTC

Published as a hybrid-warfare signal with a public source and reviewer-approved assessment bands. See the methodology for how records are assessed.

Raw record

{
  "id": "89aa3e9a-6036-4f8b-a0be-99935ac8ea2e",
  "url": "https://rus.delfi.lv/57862/abroad/56324468/foto-na-kurshskoy-kose-nayden-rossiyskiy-razvedyvatelnyy-sonar",
  "source": "csv-import",
  "status": "approved",
  "category": "Intelligence & Espionage",
  "subcategory": "Signals/Technical Intelligence (SIGINT/TECHINT)",
  "incident_type": "Electronic surveillance",
  "country": "Lithuania",
  "source_reliability": "C",
  "info_credibility": "3",
  "tags": [
    "Russian sonar",
    "Curonian Spit",
    "hydroacoustic sonar",
    "Lithuania",
    "submarine detection",
    "intelligence gathering",
    "Baltic Sea"
  ],
  "nodes": [],
  "countries": [],
  "where_text": "Land",
  "headline": null,
  "description": "On February 3, 2024, a civilian reported finding an unknown device with Russian inscriptions on the Curonian Spit in Lithuania to the Lithuanian Navy. Military experts identified the device as a Russian-made hydroacoustic sonar used for intelligence collection, submarine detection, and positioning. The device was not functioning and is currently held by the Lithuanian Navy. According to Lithuanian Armed Forces, the sonar uses hydroacoustic sensors to detect movement and passage of large underwater objects nearby. Similar Russian hydroacoustic sonar devices were previously found in 2021 in the Baltic Sea off Lithuania and in the Atlantic Ocean near the southern coasts of the United Kingdom and Ireland.",
  "summary_short": "On February 3, 2024, Lithuanian Armed Forces reported the discovery of a Russian hydroacoustic sonar used for submarine detection on the Curonian Spit.",
  "summary_extended": "On February 3, 2024, Lithuanian Navy received a report from a civilian about finding an unusual device with Russian inscriptions on the Curonian Spit. Military experts identified it as a Russian-made hydroacoustic sonar used for intelligence gathering and locating submarines. The device was not operational and is currently stored with the Lithuanian Navy. Lithuanian Armed Forces noted this sonar uses hydroacoustic sensors to detect and track large underwater objects nearby. Similar Russian sonar devices were found in 2021 near Lithuania in the Baltic Sea and near the southern coasts of the United Kingdom and Ireland in the Atlantic Ocean.",
  "actor_primary": "Russian hydroacoustic sonar manufacturer",
  "target_primary": null,
  "location_text": "Curonian Spit",
  "location_region": null,
  "location_coordinates_lat": 55.169438,
  "location_coordinates_lon": 23.881275,
  "location_precision": "Approximate",
  "is_aggressor_signal": true,
  "signal_type": "HYBRID_SIGNAL",
  "is_hybrid_war_signal": true,
  "classification_complete": true,
  "hybrid_signal_complete": true,
  "classification_confidence": "High",
  "classification_rationale": "The event involves discovery of a Russian hydroacoustic intelligence device dedicated to submarine detection found on Lithuanian territory, clearly indicating hostile espionage activity consistent with Russian hybrid warfare methods.",
  "event_time_utc": "2024-02-03T00:00:00.000Z",
  "end_time_utc": null,
  "event_time_confidence": "pm24h",
  "created_at": "2026-02-14T12:22:52.558Z",
  "updated_at": "2026-11-08T20:13:20.636Z",
  "reliability_band": "strong",
  "location_precision_band": "approximate",
  "time_precision_band": "within_24h",
  "severity_band": "moderate",
  "attribution_confidence_band": "low",
  "attribution_basis": "single_source"
}

Public assessmentReliability: StrongSeverity: ModerateAttribution: LowSingle sourceTime: Same dayLocation: Approximate

Source reliability

Info credibility

Event time

Feb 3, 2024, 00:00 UTC

Event time confidence

pm24h

Location

Curonian Spit

Primary actor

Russian hydroacoustic sonar manufacturer

Country

Lithuania

Tags

Russian sonar, Curonian Spit, hydroacoustic sonar, Lithuania, submarine detection, intelligence gathering, Baltic Sea

Loading signal...

{ "id": "89aa3e9a-6036-4f8b-a0be-99935ac8ea2e", "url": "https://rus.delfi.lv/57862/abroad/56324468/foto-na-kurshskoy-kose-nayden-rossiyskiy-razvedyvatelnyy-sonar", "source": "csv-import", "status": "approved", "category": "Intelligence & Espionage", "subcategory": "Signals/Technical Intelligence (SIGINT/TECHINT)", "incident_type": "Electronic surveillance", "country": "Lithuania", "source_reliability": "C", "info_credibility": "3", "tags": [ "Russian sonar", "Curonian Spit", "hydroacoustic sonar", "Lithuania", "submarine detection", "intelligence gathering", "Baltic Sea" ], "nodes": [], "countries": [], "where_text": "Land", "headline": null, "description": "On February 3, 2024, a civilian reported finding an unknown device with Russian inscriptions on the Curonian Spit in Lithuania to the Lithuanian Navy. Military experts identified the device as a Russian-made hydroacoustic sonar used for intelligence collection, submarine detection, and positioning. The device was not functioning and is currently held by the Lithuanian Navy. According to Lithuanian Armed Forces, the sonar uses hydroacoustic sensors to detect movement and passage of large underwater objects nearby. Similar Russian hydroacoustic sonar devices were previously found in 2021 in the Baltic Sea off Lithuania and in the Atlantic Ocean near the southern coasts of the United Kingdom and Ireland.", "summary_short": "On February 3, 2024, Lithuanian Armed Forces reported the discovery of a Russian hydroacoustic sonar used for submarine detection on the Curonian Spit.", "summary_extended": "On February 3, 2024, Lithuanian Navy received a report from a civilian about finding an unusual device with Russian inscriptions on the Curonian Spit. Military experts identified it as a Russian-made hydroacoustic sonar used for intelligence gathering and locating submarines. The device was not operational and is currently stored with the Lithuanian Navy. Lithuanian Armed Forces noted this sonar uses hydroacoustic sensors to detect and track large underwater objects nearby. Similar Russian sonar devices were found in 2021 near Lithuania in the Baltic Sea and near the southern coasts of the United Kingdom and Ireland in the Atlantic Ocean.", "actor_primary": "Russian hydroacoustic sonar manufacturer", "target_primary": null, "location_text": "Curonian Spit", "location_region": null, "location_coordinates_lat": 55.169438, "location_coordinates_lon": 23.881275, "location_precision": "Approximate", "is_aggressor_signal": true, "signal_type": "HYBRID_SIGNAL", "is_hybrid_war_signal": true, "classification_complete": true, "hybrid_signal_complete": true, "classification_confidence": "High", "classification_rationale": "The event involves discovery of a Russian hydroacoustic intelligence device dedicated to submarine detection found on Lithuanian territory, clearly indicating hostile espionage activity consistent with Russian hybrid warfare methods.", "event_time_utc": "2024-02-03T00:00:00.000Z", "end_time_utc": null, "event_time_confidence": "pm24h", "created_at": "2026-02-14T12:22:52.558Z", "updated_at": "2026-11-08T20:13:20.636Z", "reliability_band": "strong", "location_precision_band": "approximate", "time_precision_band": "within_24h", "severity_band": "moderate", "attribution_confidence_band": "low", "attribution_basis": "single_source" }