French citizen arrested after Warsaw metro tunnel intrusion, faces attempted infrastructure attack charge

The incident

On 24 June 2026, at around 7:00 a.m., the alarm systems of the Warsaw Metro detected an unauthorised person in the tunnel of line M1 between the Ursynów and Służew stations. A 22-year-old French citizen was detained by police officers from the Warsaw II District Police Headquarters as he exited the tunnel at the Służew station.

After 7 a.m. our alarm systems detected an unauthorised person in the metro tunnels between Ursynów and Służew stations. The man was detained by a police patrol as he was leaving the tunnels at Służew station.

Morning disruption and first sweep

All ten stations on the Mokotów and Ursynów sections were immediately closed. Train traffic was suspended for about four hours while police combed the tunnels for pirotechnic, chemical, and biological threats. The detainee had no dangerous items on him, was sober, and a blood sample was taken for toxicology tests. Replacement bus services were overcrowded as commuters struggled to reach the city centre.

Second inspection and damage

Later in the afternoon, police re-entered the tunnels because the detainee had refused to cooperate and could not explain why he had entered the restricted area. This time, officers discovered damage to the protective housing of the ventilation system – a so-called intake‑exhaust unit – as reported by RMF FM. No explosives or weapons were found during either sweep.

Investigation and charges

According to unofficial information from the news portal Onet, the Frenchman has been preliminarily charged under Article 254a of the Polish Criminal Code, which criminalises acts that damage, destroy, or render unusable any element of a metro line, causing disruption, with a penalty of six months to eight years in prison. The man initially tried to explain his actions but later stopped answering questions, investigators said.

He didn’t want to say anything. So we don’t yet know the reasons why he entered the tunnel. That will be the subject of our investigation. No dangerous items were found on the man.

Arrest and transfer to military division

On 26 June, the Warsaw District Prosecutor’s Office announced that a court had ordered the temporary arrest of the French citizen for three months. The case, initially handled by the Warsaw-Mokotów District Prosecutor’s Office, has been taken over by the 8th Military Division of the Warsaw District Prosecutor’s Office. A prosecutor’s spokesperson confirmed the ongoing proceedings but declined to give details.

The detained French citizen has been temporarily arrested for a period of three months. At this time, due to the good of the proceedings, we are not providing any further information about its course or findings.