Islamabad, March 28: At least 23 people were killed and dozens injured in clashes between the rival Sunni and Shia Muslims in Pakistan's North-West Frontier Province, officials said Friday.

"Eight people were killed Friday and 15 died Thursday night in the firefight between Sunni-dominated Orakzai and Shia Kachai tribes in Kohat district," said the area chief civilian officer Kamran Zeb.

"The death toll might increase as we are receiving reports from three villages where the fighting is going on that many dead bodies are lying in the streets," he added.

The fighting started five days earlier when armed men from the two tribes exchanged fire during a tribal jirga meeting. Heavy weapons were used in the conflict that has so far claimed more than 50 lives.