Zambia, often praised for its democracy and healthy economy, now faces a presidential election with high tensions on both fronts.

This southern African country votes Thursday amid concerns about political violence and local media restrictions, as well as economic problems caused by the drop in the price of its main export, copper.

Candidates include President Edgar Lungu, who has been in office for just a year and a half, and businessman Hakainde Hichilema of the opposition United Party for National Development. Lungu took office in January 2015 after the death of President Michael Sata.

For the first time, a candidate must win more than 50 percent of the vote or face a runoff election.

The head of the electoral commission has called the violence ahead of this year's vote unprecedented.