Gunmen in Iran kill 9 foreign nationals near Pakistan border
"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 Israel's war on Gaza.
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.
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.
The two countries, however, announced last Monday that they had decided to de-escalate and resumed diplomatic missions with the two ambassadors returning to their posts.