Incident took place in Kech district in southwestern Balochistan province, which shares a long border with Afghanistan and Iran.
Pakistan’s army said attackers from Iran killed four of its border patrol soldiers.
The soldiers were part of a routine border patrol operating along the Pakistan-Iran border when fighters attacked in the Jalgai sector of Kech district, the military said in a statement on Saturday.
There was no immediate claim of responsibility for the attack.
“A group of terrorists operating from Iranian side attacked a routine border patrol of Pakistani security forces operating along Pakistan-Iran Border,” the military’s media wing ISPR said in a statement.
“Necessary contact with Iranian side is being made for effective action against terrorists on the Iranian side and to prevent such incidents in future.”
It identified the casualties as Sher Ahmed, Muhammad Asghar, Muhammad Irfan and Abdur Rasheed.
Pakistan and Iran share more than 900km (45 miles) of border. There have been several security incidents in the past.
Rebel Baluch nationalist groups in the area say they are fighting for a greater share of regional resources. The Baluch groups operate on both sides of the border.
In January, Pakistani Prime Minister Shahbaz Sharif condemned the killing of four security officials along the border with Iran in Baluchistan. He said, “We expect Iran will ensure that its soil is not used for cross-border attacks.”
In January, at least 13 people were wounded after an explosion in a passenger train in the province’s Bolan district.
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