On January 4, 2026, Greece's Civil Aviation Authority detected massive airborne radio frequency interference disrupting almost all communication frequencies in Athens FIR, prompting deployment of a technical investigation aircraft and reducing air traffic flow.

Cyber & Information WarfareCyber AttacksAttacks on critical infrastructure (energy, transport, hospitals)

AggressorDefense

Summary

The Hellenic Civil Aviation Authority (ΥΠΑ) reported on January 4, 2026, a large-scale and unprecedented interference event affecting nearly all radio frequencies servicing Athens FIR starting 08:59 local time. The interference manifested as continuous unintentional emissions causing significant communication outages including HELLAS COM and critical operational telephone lines. The ΥΠΑ immediately convened a Crisis Response Team under the direction of its leadership and activated coordinated efforts with technical experts from OTE and the regulatory EETT, along with cooperation from EUROCONTROL. To precisely identify the interference source, a specially equipped aircraft with electronics technicians was urgently launched from midday to conduct airborne detection and analysis. To preserve flight safety, the air traffic controllers at Athens FIR reduced aircraft handling capacity initially to 35 flights per hour before slightly increasing it to 45 per hour in the afternoon. Regional signal transmission stations in Hymettus, Pelion, Thasos, Acarnania, Monastiri and Geraneia were also inspected on-site. This event represents a serious disruption to essential aviation communication infrastructure with geographic breadth and temporal persistence previously unseen in Greece.

Classification

Confidence: High

Classified as aggressor event due to description of massive airborne frequency interference disrupting critical aviation communications in Greece. Defense preparation classification applies because Greek Civil Aviation Authority launched a crisis response, coordinated with EUROCONTROL, deployed a technical investigation aircraft, and adjusted flight capacity to maintain safety.

Source URL

https://skai.gr/news/greece/ypa-gia-fir-athinon-maziki-paremvoli-sxedon-se-oles-tis-syxnotites

Open source

Provenance

Publisher: extension
Submitted: Feb 1, 2026, 00:14 UTC
Last updated: Nov 4, 2026, 08:35 UTC
Event time: Jan 4, 2026, 06:59 UTC

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

Raw record

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  "id": "ab9ebe22-bf3f-4c25-8b89-ddd6cf099a7a",
  "url": "https://skai.gr/news/greece/ypa-gia-fir-athinon-maziki-paremvoli-sxedon-se-oles-tis-syxnotites",
  "source": "extension",
  "status": "approved",
  "category": "Cyber & Information Warfare",
  "subcategory": "Cyber Attacks",
  "incident_type": "Attacks on critical infrastructure (energy, transport, hospitals)",
  "country": "Greece",
  "source_reliability": "C",
  "info_credibility": "3",
  "tags": [
    "Greece",
    "Athens FIR",
    "radio interference",
    "aviation safety",
    "airborne jamming",
    "EUROCONTROL",
    "uav",
    "EETT",
    "cyber attack",
    "critical infrastructure disruption"
  ],
  "nodes": [],
  "countries": [],
  "where_text": "Airspace",
  "headline": null,
  "description": "On January 4, 2026, starting around 08:59 local time (06:59 UTC), the Hellenic Civil Aviation Authority (ΥΠΑ) detected unprecedented mass radio frequency interference across nearly all frequencies serving the Athens Flight Information Region (FIR). The interference presented as continuous, involuntary emissions, severely degrading communications and causing HELLAS COM lines and operational telephone communications to fail. The interference persisted over a wide geographic area affecting multiple regional transmission units including Hymettus, Pelion, Thasos, Acarnania, Monastiri, and Geraneia. In response, ΥΠΑ assembled a Crisis Response Team and coordinated closely with EUROCONTROL and the Greek operator OTE to locate and troubleshoot the source. At midday, a specially equipped ΥΠΑ aircraft containing electronic specialists and technicians from the Hellenic Telecommunications and Post Commission (EETT) was urgently deployed to investigate the airborne origin of the interference. Due to flight safety concerns, the Athens Control Center reduced the flow of aircraft to 35 per hour initially, later raising it to 45 per hour after 16:00 local time. This incident marks a significant and unprecedented interference event with major impact on critical aviation communications in Greek airspace.",
  "summary_short": "On January 4, 2026, Greece's Civil Aviation Authority detected massive airborne radio frequency interference disrupting almost all communication frequencies in Athens FIR, prompting deployment of a technical investigation aircraft and reducing air traffic flow.",
  "summary_extended": "The Hellenic Civil Aviation Authority (ΥΠΑ) reported on January 4, 2026, a large-scale and unprecedented interference event affecting nearly all radio frequencies servicing Athens FIR starting 08:59 local time. The interference manifested as continuous unintentional emissions causing significant communication outages including HELLAS COM and critical operational telephone lines. The ΥΠΑ immediately convened a Crisis Response Team under the direction of its leadership and activated coordinated efforts with technical experts from OTE and the regulatory EETT, along with cooperation from EUROCONTROL. To precisely identify the interference source, a specially equipped aircraft with electronics technicians was urgently launched from midday to conduct airborne detection and analysis. To preserve flight safety, the air traffic controllers at Athens FIR reduced aircraft handling capacity initially to 35 flights per hour before slightly increasing it to 45 per hour in the afternoon. Regional signal transmission stations in Hymettus, Pelion, Thasos, Acarnania, Monastiri and Geraneia were also inspected on-site. This event represents a serious disruption to essential aviation communication infrastructure with geographic breadth and temporal persistence previously unseen in Greece.",
  "actor_primary": "Υπηρεσία Πολιτικής Αεροπορίας (ΥΠΑ)",
  "target_primary": null,
  "location_text": "FIR Athens, including regional transmission units at Hymettus, Pelion, Thasos, Acarnania, Monastiri, Geraneia",
  "location_region": null,
  "location_coordinates_lat": null,
  "location_coordinates_lon": null,
  "location_precision": "Regional",
  "is_aggressor_signal": true,
  "signal_type": "DEFENSE_PREP_SIGNAL",
  "is_hybrid_war_signal": true,
  "classification_complete": true,
  "hybrid_signal_complete": true,
  "classification_confidence": "High",
  "classification_rationale": "Classified as aggressor event due to description of massive airborne frequency interference disrupting critical aviation communications in Greece. Defense preparation classification applies because Greek Civil Aviation Authority launched a crisis response, coordinated with EUROCONTROL, deployed a technical investigation aircraft, and adjusted flight capacity to maintain safety.",
  "event_time_utc": "2026-01-04T06:59:00.000Z",
  "end_time_utc": null,
  "event_time_confidence": "unknown",
  "created_at": "2026-02-01T00:14:43.368Z",
  "updated_at": "2026-11-04T08:35:32.139Z",
  "reliability_band": "strong",
  "location_precision_band": "regional",
  "time_precision_band": "unknown",
  "severity_band": "significant",
  "attribution_confidence_band": "medium",
  "attribution_basis": "single_source"
}

Public assessmentReliability: StrongSeverity: SignificantAttribution: MediumSingle sourceTime: UnknownLocation: Regional

Source reliability

Info credibility

Event time

Jan 4, 2026, 06:59 UTC

Event time confidence

unknown

Location

FIR Athens, including regional transmission units at Hymettus, Pelion, Thasos, Acarnania, Monastiri, Geraneia

Primary actor

Υπηρεσία Πολιτικής Αεροπορίας (ΥΠΑ)

Country

Greece

Tags

Greece, Athens FIR, radio interference, aviation safety, airborne jamming, EUROCONTROL, uav, EETT, cyber attack, critical infrastructure disruption

Loading signal...

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