RIO DE JANEIRO -- A small plane crashed Saturday in the Amazon with 20 people on board -- 16 of whom are still missing, a Brazilian official said.
The plane went down in a river about 50 miles southwest of state capital Manaus, said a spokesman for the Amazonas state government, who spoke on condition of anonymity in line with department policy.
Another official confirmed the crash to a local news outlet.
"The survivors said they saw one of the motors of the plane stop," Daniel Guedes, a police official in the city of Manacapuru near the crash site, told the Internet news portal Terra.
The plane -- being used as an air taxi, a common practice in the thick jungle areas of Brazil -- crashed into the Manacapuru river about 3:30 p.m. Saturday.
A cause for the crash was not yet known.
The state spokesman said rescue officials are on the scene and searching for other survivors, but so far just the four have been found.
Guedes told Terra the plane had left the city of Coari, 225 miles southwest of Manaus. The flight's destination was not immediately known.