Heathrow Terminal 4 Reopens After Police Find No Hazardous Substance

Published: 09 September 2025. The English Chronicle Desk

Heathrow Airport’s Terminal 4 reopened on Monday evening after authorities confirmed that no hazardous substance was present, following an incident that prompted an emergency response and temporary evacuation.

The Metropolitan Police reported that around 20 people had reported injuries, though none were deemed life-threatening or serious. A thorough investigation by specialist officers, supported by the London Fire Brigade (LFB) and London Ambulance Service, found no trace of any harmful material at the scene. One person was taken to hospital, while the remaining 20 were treated and discharged at the airport.

According to the police, the incident began at 16:56 BST on Monday, 8 September, when officers were called to a “potential hazardous materials incident” at Terminal 4. Emergency services swiftly responded, with fire crews from Feltham, Heathrow, Wembley, and surrounding stations attending to ensure safety.

The London Fire Brigade confirmed that its response was gradually being stood down as investigations continued, while Heathrow Airport assured passengers via social media that the terminal was safe to reopen by 20:27 BST. The airport stated it was making every effort to ensure flights continued as scheduled, and noted that only minor delays were expected.

Earlier in the evening, authorities had advised passengers to avoid traveling to Terminal 4. National Rail Enquiries also reported that trains were temporarily unable to stop at the terminal due to the ongoing emergency. Social media posts from passengers showed travelers waiting outside the airport, some wrapped in foil blankets provided by emergency services.

Transport Secretary Heidi Alexander said she was closely monitoring the situation, receiving updates from both the airport and emergency personnel on the ground.

Heathrow, the busiest airport in the United Kingdom, has now resumed normal operations at Terminal 4, though the cause of the incident remains under investigation. Authorities have urged passengers to check for updates before traveling and thanked emergency services for their rapid response.