Pakistan’s air force launched retaliatory airstrikes against Iran Thursday morning with the aim of taking out militant hideouts, in an attack that killed at least seven persons and sent tensions between the neighboring nations soaring.

The strikes in Iran’s Sistan and Baluchestan province followed Tuesday’s Iranian attack on Pakistan that killed two children in the southwestern Baluchistan province. The attacks Tuesday and Thursday appeared to target separate Baluch militant groups that the two countries say find safe havens in the other. Earlier in the week, Iran also attacked sites in its old foe, Iraq.

Washington’s response to Iranian aggression has thus far been tepid. Following Tuesday’s attack, Secretary Blinken at Davos chose to speak about a “pathway to a Palestinian state.” Such language of appeasement was likely to please the Iranian foreign minister, Hossein Amir-Abdollahian, who was also attending the Davos forum. 

Although there was no meeting between Messrs Blinken and Amir-Abdollahian on Wednesday, the latter stated with trademark perfidy that “we are witnessing genocide in Gaza and the West Bank, this means that war is ongoing, so there is possibility of extension.”

How the escalation in central Asia will affect Iran’s deployment of its proxies to attack American interests in the wider region was not immediately clear, but on Wednesday Washington carried out its fourth round of strikes this week against the Iran-backed Houthis, who have been attacking ships in the Red Sea from their bases in Yemen and appear to be as yet undeterred.

Pakistan’s fresh strikes will imperil diplomatic relations between Islamabad and Tehran, as Iran and nuclear-armed Pakistan have long regarded each other with suspicion over militant attacks.

The attacks also raised the threat of violence spreading in a Middle East unsettled by Israel’s war against Hamas in the Gaza Strip. Iran also staged airstrikes late Monday in Iraq and Syria over an Islamic State-claimed suicide bombing that killed more than 90 people earlier this month. Iraq has recalled its ambassador from Iran for consultations.

Pakistan’s foreign ministry described their attack as “a series of highly coordinated and specifically targeted precision military strikes.”

“This morning’s action was taken in light of credible intelligence of impending large scale terrorist activities,” the foreign ministry said in a statement. “This action is a manifestation of Pakistan’s unflinching resolve to protect and defend its national security against all threats.”

Pakistan’s caretaker prime minister, Anwaarul-Haq-Kakar, who was in Davos to attend the World Economic Forum, cut his trip short to return home, the foreign ministry spokesman, Mumtaz Zahra Baloch, said. The foreign minister, Jalil Abbas Jilani, is also returning home from a trip to Uganda.

The Baluch Liberation Army, a separatist group, said in a statement that the strikes targeted and killed its people. “Pakistan will have to pay a price for it,” the group warned. 

“Now the Baluch Liberation Army will not remain silent. We will avenge it and we announce war on the state of Pakistan.”

Pakistan named its operation “Marg Bar Sarmachar.” In Farsi, “marg bar” means “death to.” It has been a famous saying in Iran since its 1979 Islamic Revolution used it to refer to both America and Israel. In the local Baluch language, “sarmachar” means guerrilla, and it is used by the militants operating in the cross-border region.

Iranian state television, quoting an anonymous official after the strike, said Tehran strongly condemned the attack and “demanded an immediate explanation” from Pakistan. Several insurgent groups operate in Iran and Pakistan. They all have a common goal of an independent Baluchistan for ethnic Baluch areas in Afghanistan, Iran, and Pakistan.

Thursday’s development came a day after Pakistan recalled its ambassador to Tehran because of Tuesday’s strikes by Iran inside Pakistan’s southwestern Baluchistan province. Iran claimed it targeted bases for a militant Sunni separatist group. It drew strong condemnation from Pakistan, which denounced the attack as a “blatant violation” of its airspace and said it killed two children.

The risk of escalation remained Thursday as Iran’s military will begin a planned annual air defense drill from its port of Chabahar near Pakistan all across the south of the country to Iraq. The drill, Velayat 1402, will include live fire from aircraft, drones, and air defense systems.

Iran and Pakistan share a 560-mile, largely lawless border in which smugglers and militants freely pass between the two nations. The route is also key to global opium shipments coming out of Afghanistan. For both Iran and Pakistan, the cross-border attacks renew questions about the preparedness of their own militaries, particularly their radar and air defense systems.

For Pakistan, such systems are crucial as tensions always remain at a low boil with India, its nuclear-armed rival. Their equipment has long been deployed on the frontier, rather than its border with Iran. For Iran, it relies on those systems against potential strikes by what it sees as its main enemy, America.

There are also complex geopolitical considerations in the tensions. Pakistan’s military relies on American, Chinese, and French fighter jets for its air force — meaning some of those foreign weapons were used in Thursday’s attack.

Communist China, a crucial partner in both countries, had urged restraint. Beijing is a key regional player and has a major Belt and Road development in Gwadar port in Pakistan’s Baluchistan province.