According to police a young woman onboard a flight from Brazil to Texas died mid-flight.

The American Airlines flight had departed Sao Paolo, Brazil just after 1a.m. on Wednesday and was heading to Texas’ Dallas-Fort Worth International Airport when the flight crew alerted Bush Intercontinental Airport in Houston they had a sick passenger on board and would need to land before Dallas. It landed in Houston at around 6:30 a.m.

When the plane landed in Houston, the 25-year-old woman, whose name has not been released, was already dead.

Houston police said that 8 hours into the flight, the young woman went into medical distress. Members of the flight crew along with a doctor on board performed unspecified medical procedures but were unable to save her.

Police are still investigating and have not yet determined a cause of death, but stated there were no signs of trauma.

The American Airlines’ plane, Flight 962, was a Boeing 777. Roughly 220 passengers were aboard the plane as well as 14 crew members.

Three hours after landing in Houston, Flight 962 finally left for Dallas.