ABUJA, Nigeria

The governorship elections in three critical Nigerian states were marred by violence, observers said on Sunday.

Over 5 million voters on Saturday voted to elect governors of the coastal oil-rich Bayelsa State, southern Imo State and north-central Kogi State amid violence and unrest.

“Some gunmen opened fire in southeast Imo State while the voting was going on,” Ezenwa Nwagwu, an observer and chairman of an election reforms group in Nigeria, told Anadolu.

Similar incidents were reported in Kogi State where a politician was killed a day before the poll.

Nwagwu said elections in these three states have always been a nightmare for electoral commission in the country and security agencies due to tough contest and violence.

In Nigeria, governors are powerful political leaders and the economic viability of the three states with huge revenue from crude oil, natural gas, zinc and iron ore further make the stakes higher, Emmanuel Ojuwu, a former police chief and security expert, told a local television channel.

Counting of the votes started on Sunday in the West African country which has been battling terror groups in its northeastern area since 2009.