DAR ES SALAAM, Aug. 15 (Xinhua) -- A court in northern Tanzania on Wednesday sentenced three people to 20 years in jail after finding them guilty of illegal possession of two pieces of ivory worth 15,000 U.S. dollars.

In its ruling, the Serengeti District Resident Magistrate's Court jailed Paul Ryoba, 38, Petro Mikwabe, 42, and Yagara Mang'era, 31, to 20 years imprisonment each.

Reading the judgement, the magistrate said the convicts were found guilty of entering the Serengeti National Park and hunting down elephants without valid permits as well as possessing the national trophies illegally.

In their defense, the convicts asked the court to have mercy on them on grounds that they had families to take care of.

They were arrested on January 13, 2017 in the Serengeti National Park in Serengeti district in Mara region.