The deadly attack follows rare military action in the porous border region of Baluchistan -- split between the two nations -- that had stoked regional tensions already inflamed by the Israel-Hamas war

Unidentified gunmen killed nine Pakistani workers in a restive south-eastern border area of Iran on Saturday, as confirmed by Pakistan’s ambassador and a rights group. This incident happened amidst ongoing efforts by the two countries to reconcile their relations following tit-for-tat attacks.

“According to witnesses, this morning unknown armed men killed nine non-Iranians in a house in the Sirkan neighbourhood of Saravan city” in Sistan-Baluchistan province, the Mehr news agency reported.

So far, no group or individuals had claimed responsibility, the agency added.

The deadly attack follows rare military action in the porous border region of Baluchistan — split between the two nations — that had stoked regional tensions already inflamed by the Israel-Hamas war.

Sistan-Baluchistan is one of the few mainly Sunni Muslim provinces in Shiite-dominated Iran.

It has seen persistent unrest involving cross-border drug-smuggling gangs and rebels from the Baluchi ethnic minority, as well as jihadists.

The Baluch rights group Haalvash said on its website that the victims were Pakistani labourers who lived at an auto repair shop where they worked. Three others were wounded, it said.

Iran’s state media identified the dead only as foreign nationals and said no individuals or groups had claimed responsibility for the shootings in Saravan in restless Sistan-Baluchestan province.

“It is a horrifying and despicable incident and we condemn it unequivocally,” Pakistani Foreign Ministry spokesperson Mumtaz Zahra Baloch said. “We are in touch with Iranian authorities and have underscored the need to immediately investigate the incident and hold to account those involved.”

On January 18, Pakistan launched air strikes on “militant targets” in Iran, two days after Iran had launched strikes on its territory.

Tehran said it had targeted Jaish al-Adl, a jihadist group which has carried out a spate of deadly attacks in Iran in recent months.

Formed in 2012, the group is blacklisted by Iran as a “terrorist” organisation.

The Iranian strikes, which Pakistan said killed at least two children, drew a sharp rebuke from Islamabad, which recalled its ambassador from Tehran and blocked Iran’s envoy from returning to Islamabad.

Tehran also summoned Islamabad’s charge d’affaires over Pakistan’s strikes, which left at least nine people dead.