A helicopter donated to the Tanzanian government to help with anti-poaching operations crashed on Saturday, killing all four people on board, police said.
A police spokeswoman said the Robertson R44 helicopter, worth $500,000, had recently been given to Tanzania by the Howard G. Buffett Foundation.
She said the helicopter went down in the Kipunguni area of the Indian Ocean port city of Dar es Salaam.
"Two pilots from the police force, a civilian pilot and a police officer were in the ill-fated aircraft," police spokeswoman Advera Senso told AFP.
An investigation was underway to establish the cause of the apparent accident.
The Howard G. Buffett Foundation is a private family foundation set up by the businessman and former politician son of US billionaire investor Warren Buffet.