Pakistan has condemned Iran for violating its airspace after a missile attack on Tuesday killed at least two children and wounded three others.

The missiles targeted two bases belonging to Jaish al-Adl, a militant group that has before claimed responsibility for attacks on Iranian security forces along the border with Pakistan, Iranian state media said.

It comes a day after Iran struck northern Iraq in what it claimed was an attack on an Israel spy base. The Islamic republic is already facing pressure for escalating conflict in the Middle East through proxies like the Houthis.

The Pakistani government lodged a complaint with Iran over the civilian deaths in the latest airstrike, and has warned that “the responsibility for the consequences will lie squarely with Iran”.

Iranian reports have described the missiles as landing in Pakistan’s Balochistan province, though the country’s authorities have not specified where the attacks occurred.

Jaish al-Adl, or the “Army of Justice”, is a Sunni militant group founded in 2012, and primarily operates in Pakistan.

The group claimed it was behind an attack in December, when militants attacked a police station in southeastern Iran. Iranian state media said then that 11 security personnel were killed and several others injured.

The incident involving Pakistan adds to tensions in the Middle East, coming hours after Iranian strikes in Iraq and Syria – the country’s first direct military operation since war broke out last October between Israel and Hamas.

Fears have grown that the Israel and Hamas conflict, largely taking place in the Gaza Strip, a Palestinian territory, could engulf the Middle East in a wider war.

Regional fighting, if it were to occur, would be devastating to the region where many countries’ economies are struggling to recover post-pandemic, amid other political and social challenges.

Accusations have flown back and forth over who is to blame for increasing tensions.

Earlier this week, Hossein Amir-Abdollahian, the Iranian foreign minister, accused the US and UK of making a “strategic mistake” by launching strikes in the Red Sea against Yemen’s Houthi rebels, another group backed by Iran.

The US, and other nations, however, have warned groups like the Houthis to back down and to stop launching attacks, which the movement has said are to support Hamas in its war against Israel.

Those assaults have largely halted commercial shipping through the Red Sea, a key route that connects Asia to the Middle East and Europe.