Afghan forces on Friday opened fire on Pakistani security personnel in the restive Balochistan province, killing at least three people, including a woman, and injuring 17 others, officials said.

The Afghan troops started shelling in Kali Luqman and Kali Jahangir area of Chaman district. Security officials said that the purpose was to target two Pakistani check posts in the area. Pakistan forces retaliated to the fire.

Medical Superintendent of Chaman Civil Hospital Akhtar said three persons including a woman died and 17 others were injured in the firing from the Afghan side.

Pakistan army's media wing, the Inter-Services Public Relations (ISPR), earlier released a statement saying Afghan Border Police opened fire on Frontier Corps (FC) personnel detailed for the security of a census team in Chaman.

It was not known immediately why the firing started. Some reports suggested that intermittent firing was still going on.

Pakistan sealed the Friendship Gate at the Chaman border crossing for all kinds of transportation due to the firing.

It was the second time this year that the Chaman border crossing was sealed.

In February, it was closed along with other crossings after a series of terrorist attacks, which Pakistan said were launched by militants hiding in Afghanistan.