Passenger Dies After Man Runs onto Runway and is Struck by Plane

A deadly runway incident at Denver International Airport is now at the center of a sweeping lawsuit, with attorneys alleging that security failures and problems at a behavioral health facility helped set the stage for a terrifying encounter involving a Frontier Airlines jet.

More than 70 passengers, crew members and an air traffic controller are involved in the lawsuit stemming from the May 8 incident, when 41-year-old Michael Mott breached the airport’s perimeter and entered an active runway as Frontier Airlines Flight 4345 was preparing to take off for Los Angeles.

Mott was struck by the Airbus A321neo and died at the scene. Denver’s medical examiner later ruled his death a suicide.

The collision forced the pilots to abort the takeoff as an engine caught fire and smoke entered the aircraft. The 231 passengers and crew members aboard were evacuated using emergency slides.

Officials initially reported 12 minor injuries, including five people who were taken to hospitals.

But a lawsuit filed Sept. 17 in Denver District Court now alleges the consequences were even more serious.

Attorneys representing the plaintiffs say passenger Silva Ermelinda de Cervantes died May 16, eight days after the runway incident, following exposure to smoke, toxic fumes and other combustion byproducts aboard the aircraft.

The complaint includes a wrongful death claim on behalf of de Cervantes’ estate.

However, that alleged connection has not been established as fact.

The Weld County Coroner’s Office said it reviewed the circumstances surrounding de Cervantes’ death and classified the manner of death as natural. Her primary care clinician attributed her death to natural disease, according to Colorado Public Radio. No autopsy was performed.

Attorneys for the family contend that the runway emergency and subsequent exposure contributed to her death.

The lawsuit also alleges de Cervantes suffered a stroke in the days following the incident.

Lawsuit Targets Airport Security

The complaint names the City and County of Denver, Denver International Airport officials, aviation security contractor Covenant Aviation Security and several behavioral health-related defendants.

At the center of the airport allegations is a question that emerged almost immediately after the tragedy: How was Mott able to get onto an active runway?

Authorities have said Mott climbed an airport perimeter fence before reaching Runway 17L.

According to previous reporting on the incident, he was able to scale the fence in roughly 15 seconds. About two minutes reportedly passed between his breach of the perimeter and the collision with the Frontier jet.

The plaintiffs allege Denver failed to properly secure the airport perimeter, detect Mott’s entry and stop aircraft operations before he reached the runway.

The lawsuit also accuses Covenant Aviation Security of failing to adequately monitor and patrol the perimeter.

One particularly important allegation concerns the airport’s intrusion-detection system.

According to reporting on the lawsuit, a ground sensor produced an alert before the collision. Airport officials previously said an operator who reviewed an alert believed activity near the fence was connected to deer outside the secured area.

The plaintiffs argue that a proper response to the alarm could have resulted in air traffic controllers being warned and takeoffs being halted before Mott reached Flight 4345.

Those allegations have not yet been proven in court.

The Denver City Attorney’s Office has rejected the assertion that the city is legally responsible.

A city spokesperson called the incident tragic while saying the city does not believe it bears legal responsibility for what occurred.

Questions About Mott’s Care Before His Death

The lawsuit extends well beyond airport security.

Mott had spent years moving through Colorado’s criminal justice and mental health systems before his death.

Court records examined by Colorado Public Radio showed he had previously been found incompetent to proceed in a criminal case and ultimately entered a state-funded Mental Health Transitional Living program designed to provide treatment in a less restrictive environment.

He had been placed at a residential home on South Bahama Street in Aurora.

The lawsuit alleges those responsible for Mott’s care knew he had struggled with suicidal thoughts and should have more closely supervised him.

According to the complaint, Mott had previously expressed a plan involving being struck by a vehicle.

Attorneys allege the behavioral health defendants nevertheless failed to properly supervise him, monitor his medication or account for his whereabouts before he left the home and eventually reached Denver International Airport.

Those accusations remain allegations in an ongoing civil case.

It is also not clear precisely where Mott was living immediately before his death or exactly how he traveled to the airport.

State Inspectors Had Previously Found Problems

The residential facility has faced scrutiny separate from the lawsuit.

Colorado Public Radio previously reported that state inspectors found 16 violations during an October 2025 audit of the home, including problems involving documentation of medications, case management and treatment coordination.

State officials later said the operator corrected the violations and made improvements.

The findings do not by themselves establish that those problems contributed to the May runway incident.

The home was operated by Oakwood Behavioral Health, according to state records, while Hazelbrook and related companies are among the entities named in the lawsuit.

Mott also continued to have contact with law enforcement.

About a month before his death, he was arrested in Colorado Springs on a trespassing charge and released on a personal recognizance bond.

More Than A Runway Accident

For the passengers aboard Flight 4345, the lawsuit claims the impact went far beyond the initial emergency.

Plaintiffs allege they were exposed to smoke and fumes during the aborted takeoff and evacuation and suffered a range of physical and psychological injuries.

Some say they have struggled to fly since the incident.

The suit brings 17 claims, including negligence, negligent hiring, negligent infliction of emotional distress and wrongful death, and seeks unspecified damages.

The Federal Aviation Administration said after the May incident that Flight 4345 struck a person while departing Denver for Los Angeles and confirmed that the aircraft was evacuated using emergency slides.

The FAA opened an investigation into the incident.

The lawsuit could now force a closer examination of several separate systems that were supposed to provide layers of protection — the airport perimeter, security monitoring and the supervision surrounding Mott before he reached the airport.

For now, however, many of the lawsuit’s most serious assertions — including the claim that the runway emergency caused de Cervantes’ death and allegations that particular security or behavioral health failures could have prevented the tragedy — remain disputed claims that will have to be tested through the court process.

If you or someone you know is struggling with thoughts of suicide or experiencing a mental health crisis, call or text 988 to reach the Suicide & Crisis Lifeline.