Here are some facts about the Jaish al-Adl group that was the target of the attack.
WHAT IS JAISH AL-ADL?
Jaish al-Adl (JaA) is an extremist Sunni Muslim militant group. It is an offshoot of Jundallah, founded by Abdolmalek Rigi in around 2002 and led by him until his execution by the Iranian government in 2010.
In the wake of Rigi's death, several splinter groups formed, with JaA emerging as the most influential one from around 2012.
The group operates in southeastern Iran and the western Pakistani province of Balochistan, a restive area that borders Iran and Afghanistan where the strikes took place.
WHAT ARE THE GROUP'S AIMS?
JaA, which says it seeks greater rights and better living conditions for ethnic minority Baluchis, has claimed responsibility for several attacks in recent years on Iranian security forces in Iran's southeastern province of Sistan-Baluchestan.
In its previous iteration as Jundallah, the group had pledged allegiance to Iraq-and Syria-based jihadist group the Islamic State.
The U.S. State Department has designated both Jundallah and JaA as "foreign terrorist organisations".
(Reporting by Charlotte Greenfield; Editing by Ros Russell)
