A mysterious explosion has killed the head of an Al-Aqsa Martyrs Brigade missile unit, according to reports by the Hamas-run Gaza health ministry.

The blast rocked central Gaza on Sunday morning, killing Ahmad Husan, head of the Ayman Jawda branch of the Brigade, and his 13-year-old son, Louay. Some Palestinian media reports suggest that the blast was a “work accident,” although that claim has not been verified.

The deaths came just a day after some 200 rockets and mortar shells were fired at Israeli civilian centers along the Gaza border by Hamas and allied terror groups in the most serious attacks since the 2014 Gaza war.

Israel responded by firing aerial attacks against dozens of terror targets in Gaza, including a Hamas urban-warfare training facility situated above a massive underground terror and smuggling tunnel.

The Al-Aqsa Martyrs Brigade is typically associated with the Fatah party of Palestinian Authority leader Mahmoud Abbas, but maintains a limited presence in Hamas-controlled Gaza. Fatah and Hamas have been at odds for years, with repeated attempts at reconciliation meeting with failure, frequently due to disagreements as to who will control Gaza.