Tuesday, three minors were injured and two were killed, according to Pakistan, in airstrikes launched by neighbouring Iran.
Iran stated that it targeted two compounds associated with the militant organisation Jaish al-Adl, according to a military-affiliated news agency.
Pakistan, on the other hand, vehemently opposed this, describing it as a "illegal conduct" with "serious consequences."
Pakistan has been the target of an Iranian attack in recent days, following Iraq and Syria as the third nation to be affected.
A Pakistani missile strike by Iran would be virtually unprecedented. A village was affected by the strike on Tuesday in the expansive south-western province of Balochistan, which shares a frontier with both nations.
The foreign ministry of Pakistan issued a vehement condemnation in a statement that characterised the unprovoked violation of its airspace by Iran.
The organisation characterised the occurrence as "completely abhorrent" and further expressed concern over the fact that "this unlawful action occurred despite the fact that multiple channels of communication existed between Iran and Pakistan."
Pakistan has lodged a formal complaint with a "concerned senior official" at the Iranian foreign ministry in Tehran, the capital, asserting that "Iran bears full culpability for the repercussions of this flagrant violation of Pakistan's sovereignty."
The United States condemned Iran's late Monday night ballistic missile assaults against targets in the northern Iraqi city of Irbil.
Tensions have increased throughout the Middle East since the conflict in the Gaza Strip, which Israel and the Iranian-backed Palestinian organisation Hamas have been engaged in since October 7th, when the Iranian strikes began.
Despite Iran's official posture of abstaining from involvement in a broader conflict, factions comprising its purported "Axis of Resistance" have initiated offensive activities against Israel and its allies as a show of Palestinian solidarity.
Cross-border gunfire has been observed between Israeli forces and the Hezbollah movement in Lebanon. American forces stationed in Iraq and Syria have been targeted by missiles and drones launched by Shia militias. Ships in the Red Sea have been targeted by Houthi militants originating from Yemen.
According to reports, Israel has executed airstrikes that resulted in the demise of a Hamas leader in Lebanon and a Revolutionary Guards commander in Syria. Similarly, the United States has attacked Houthi targets in Yemen and eliminated an Iraqi militia leader in an air strike in Iraq.
Decades have passed since Pakistan and Iran engaged in combat with armed separatist factions, including Jaish al-Adl, in the scarcely populated area.
Both of the governing bodies have expressed a continuous and serious worry regarding the issue of border security, which spans around 900 kilometres (559 miles) in length.
Tehran has established a connection between the organisation and the attacks on the frontier that took place a month ago, which resulted in the deaths of more than a dozen Iranian police officers.
Ahmad Vahidi, the Iranian minister of the interior at the time, stated that the responsible militants had infiltrated the country via Pakistan.
The United States Director of National Intelligence rates Jaish al-Adl as the "most active and influential" Sunni militant organisation in operation in Sistan-Baluchestan.
