Authorities on Monday picked up plane wreckage strewn across four blocks following an "unusual" crash that killed five people on Sunday in a Southern California neighborhood.
Witnesses told National Transportation Safety Board investigators the small plane came out of a cloud in one piece before its tail and wings broke off, a spokesperson said at a Monday press conference. The Cessna already began burning before it hit a Yorba Linda house, setting it ablaze.
Orange County officials identified the deceased pilot as Antonio Pastini, 75, a retired Chicago police officer. NTSB is investigating his medical history, flight experience, maintenance reports, as well as whether weather such as lightning affected the crash.
Pastini left the nearby Fullerton Municipal Airport at about 1:35 p.m., NTSB said, and flew about 10 miles before his plane began a rapid descent. Authorities said they do not know where the commercial pilot was going or his speed.
Four people inside the house died in the resulting fire, NTSB said. The coroner's office is using DNA to identify the two women and two men before notifying their families.
Two additional people in the house were injured and taken to the hospital. The sheriff's department told USA TODAY it believes additional people were in the house, but has not determined how many as the investigation focuses on the deceased.
While a plane crashing into a home is "quite unusual," and a rare type of accident, NTSB spokesperson Peter Knudson said, they do happen. A small propeller-driven plane crashed into two Connecticut homes in 2013, killing four people, including a 1-year-old and 13-year-old inside one of the homes. In 2017, a plane crashed into a San Diego home, killing two people.
Investigators on Monday collected debris from among 16 different houses, including the plane's fuselage. They will take all the aircraft parts to a Phoenix facility for examination.
While recovering the parts from such a large debris field has been challenging, NTSB said, many witnesses have come forward. The pilot did not make a distress call and NTSB said they do not know if he attempted to make an emergency landing elsewhere.
A preliminary report is expected sometime next week, NTSB said. A full investigation could take up to two years.
This article originally appeared on USA TODAY: What happened? NTSB says tail and wings broke off plane before 'unusual' California crash