Three people belonging to the Shia community were gunned downed in the Dera Ismail Khan district of Khyber Pakhtunkhwa on Sunday, said police.

The incident took place in the jurisdiction of Paroa police station.

"Initial investigations suggest that the incident was the result of an old enmity but the case's nature could change after investigation," said a police official.

The relatives of the deceased blocked the Indus Highway following the incident and claimed the killings were sectarian in nature.

The protesters dispersed after successful negotiations with government officials.