LONDON (Reuters) - Three Iranian security personnel and three militants were killed in a cross-border attack on the frontier with Pakistan on Monday, Iran’s Revolutionary Guards said in a statement posted on state media.

The Guards said on Tuesday their ground forces killed a “terrorist group” as they were trying to enter Iran near Mirjaveh border area in Sistan-Baluchestan province.

Jaish al-Adl, a Sunni militant group that has carried out several attacks on Iranian security forces in Sistan-Baluchestan, said on its Twitter account on Tuesday that they killed 11 Iranian personnel on Monday, wounding several others.

Jaish al-Adl said there were no casualties among their forces.

Sistan-Baluchestan province in southeastern Iran has long been plagued by unrest from both drug smuggling gangs and separatist militants. The population of the province is predominantly Sunni Muslim; the majority of Iranians are Shi’ites.

Three Iranian security personnel were killed by militants in April.

Jaish al-Adl say they are fighting against discrimination.