"There was trouble in Yelwa yesterday. A combined team of my men and soldiers has been drafted to maintain peace in the area, but so far I can confirm 49 people have been killed," local police chief Innocent Ilozuoke said on Wednesday.
Ilozuoke, Plateau State's police commissioner, said that most of the people who were killed had taken refuge in a church, where they had been attacked and massacred by a gang thought to be armed Fulani nomads.
He said some fighting was still going on and that the death toll was likely to rise.
Nomads and farmers, who compete for grazing land, often clash in central Nigeria, where communities are often split between ethnic and religious lines.
Yelwa is a small farming community in the Shendam local government area 300km east of Nigeria's capital Abuja.
On Monday, police said four Nigerian riot policemen were killed in tit-for-tat sectarian fighting in the central state of Plateau, bringing the death toll from two weeks of violence to 14.
More than 1,000 people have been killed in the whole Plateau state since 2001 in feuding over political and property rights which divides the three million population along religious lines.