At least six Pakistanis have been shot dead and two others wounded by Iranian border guards after they crossed the border, Pakistani officials say.

Officials say the incident occurred on Thursday on the Iranian side of the border close to Pakistan's south-western Balochistan province.

The wounded men and the corpses of the six others are yet to be handed over to the Pakistani authorities.

Reports say the men were livestock traders.

"Six of them were killed in firing by Iranian border forces and two others were wounded," local police official, Mujeebur Rehman, in the port town of Gwadar told the AFP news agency.

Earlier this month, Pakistani police detained three Iranian border guards after they allegedly crossed the border, and opened fire, killing one Pakistani man in a car they had been chasing.