Iran and Pakistan agreed Wednesday to work together to boost security along their shared border after Pakistan-based militants killed 10 Iranian border guards in the Iranian province of Sistan and Baluchestan last week. A militant group called Jaish al-Adl claimed responsibility for the attack. Earlier today, Iran’s Foreign Minister Javad Zarif – leading a delegation of senior Iranian political, military and law enforcement officials, arrived in Pakistan and held talks with Pakistan’s Prime Minister Nawaz Sharif, Interior Minister Chaudhry Nisar Ali Khan in Islamabad, and Chief of Army Staff General Qamar Javed Bajwa at the Pakistani Army headqurarters in Rawalpindi.

A statement released by Pakistan’s Interior Ministry said the two sides agreed to strengthen border security through “better coordination, greater intelligence sharing and frequent interactions” between officials of the two countries.

Comment: It is not the first time that Pakistan-based militant groups carry out attacks inside Iran, but Iranian leaders reacted more forcefully to the latest killing of the borders guards and blamed the Pakistani government’s “inaction” for it. On April 26, Iran’s President Hassan Rouhani sent a letter to Sharif, calling on Islamabad to prosecute perpetrators of an attack. The Iranian president reportedly criticized Pakistan’s “lack of necessary measures” for repeated attacks originating from Pakistan against Iranian security personnel. The Iranian foreign ministry also summoned Pakistani ambassador to protest the cross-border attack. Separately, Iran’s Foreign Ministry Spokesman Bahram Ghassemi said: “the Pakistani government should be held accountable for the presence and operation of these vicious groups on its soil.” 

Iran’s Sistan and Baluchestan, one of the country’s most impoverished province, has been a hotbed for low-intensity Sunni insurgency for a long time. It shares borders with Pakistan and Afghanistan and is a key drug trafficking route in the region. The Iranian government considers the restive region a top security priority. Hundreds of Iranian security forces have been killed in the fight against insurgents and drug smugglers in the province over the past decade. And the emergence of the so-called Islamic State in neighboring Afghanistan and Pakistan and its potential spillover into Iran’s Sunni-majority southeast has forced the Iranian government to pay more attention to the once-neglected region. Both the Islamic Revolution Guards Corps (I.R.G.C.)'s ground forces and Basij units have conducted large-scale military exercises in the southeastern region in the past one year. Last month, two separate attacks killed three I.R.G.C. officers in the area.

The latest tension between Tehran and Islamabad also comes in the wake of Iran’s “reservations” about the the appointment of Pakistan’s former army chief, retired Gen. Raheel Sharif, as the head of the Saudi-led coalition fighting in Yemen. Mehdi Honardost, Tehran’s ambassador to Islamabad, said last month that the Pakistani government “had contacted Iran before issuing the approval for General Raheel Sharif to join the military alliance, but this does not mean Iran is satisfied with or accept this decision by Pakistan.” Iran has opposed the Saudi-led counter-terrorism alliance of Islamic countries from the very outset. And the Iranian media has long expressed displeasure with the potential leadership role of the Pakistani general in the coalition.