DODOMA, Tanzania — Police in Tanzania say they are holding suspects in the killing last month of prominent South African wildlife conservationist Wayne Lotter.

Police chief Simon Sirro said in a statement Friday that some of Lotter’s possessions were seized from the suspects. He did not say how many suspects are being held.

Lotter was fatally shot in Tanzania’s commercial capital Dar es Salaam while being driven from the airport to his hotel.

Lotter helped to train thousands of game scouts throughout the East African nation. He also developed an “intelligence-based approach” against poaching that has had success in countering wildlife trafficking, according to the U.S.-based conservation group PAMS Foundation that Lotter co-founded.

Poachers have killed tens of thousands of elephants in Tanzania in the past decade.