Tanzanian president John Magufuli has condemned the killing of a British conservationist after his helicopter was shot down while he chased suspected poachers, saying five people have been arrested.
Briton Roger Gower, 37, was killed when his helicopter was gunned down by suspected poachers during a patrol of the Maswa Game Reserve in northern Tanzania, close to the world famous Serengeti National Park, on January 29.
Gower, who worked for the Friedkin Conservation Fund, had been tracking poachers after spotting the carcasses of recently killing elephants.
"This is a sad incident that must be strongly condemned," Magufuli said in a statement, ordering all those involved to be "aggressively pursued and brought to justice."
The statement said five suspects have been arrested and were being questioned by police.
Magufuli vowed to boost efforts to protect wildlife.
"I personally support the fight against poaching in our game reserves and national parks... let us join hands against the poachers," added Magufuli.
Photographs of the crashed helicopter show twisted metal, as well as apparent bullet holes in the fuselage, and smears of blood on the pilot's seat.
Gower's South African colleague, safari guide Nicky Bester, survived the helicopter crash.
Tanzania's National Parks spokesman, Pascal Shelutete, said that poachers can be "heavily armed with sophisticated military weaponry."
Ivory is sought out for jewellery and decorative objects and much of it is smuggled to China, where many increasingly wealthy shoppers are buying ivory trinkets as a sign of financial success.
It is estimated that more than 30,000 elephants are killed for their tusks every year across Africa.