TEHRAN  - Four Iranian soldiers captured by Jaishul Adl rebels near the Pakistani border in February have been freed, the Sunni extremist group and an Iranian official announced Friday.

Fars quoted Iranian lawmaker Esmail Kosari announcing the news. It did not give any details of when the release took place or what brought it about. “Four of the five abducted Iranian border guards have been handed over to Iranian embassy officials in Pakistan,” Fars quoted Kosari as saying.

Iran’s Students News agency ISNA quoted a statement from Jaishul Adl saying “Sunni clerics’ mediation led to the guards’ release ... as a sign of our goodwill”.

Fars also said the body of a slain guard had been handed over to officials of Tehran’s embassy in Pakistan. However the Fars news agency, quoting an unidentified security official said, “The soldiers were handed over some hours ago by the small terrorist group Jaishul Adl to Iranian representatives in Pakistan”.

For its part, Jaishul Adl announced the releases on its Twitter account.

“At the request of eminent Sunni clerics in Iran, the Iranian soldiers held hostage have been freed and handed over to a delegation of clerics,” it said.

The Pakistani government had repeatedly said there was no evidence the Iranian guards were on its territory. The Iranian government accused its neighbour of not doing enough to free the men and of supporting the rebels.

Pakistan authorities could not confirm the release of the abducted guards.

“They have not been released in Pakistan. We don’t know where they were kept or released.We have no indication that these Iranian border guards were kept in Pakistan,” Pakistan Foreign Ministry spokeswoman Tasnim Aslam told Reuters.

The four kidnapped guards were handed over to Iranian representatives in Pakistan but had not yet returned to Iran, Iran’s official Press TV reported.

The five soldiers, who were serving their 24-month mandatory military service, were abducted in the restive southeastern province of Sistan-Baluchestan, where Shiite-majority Iran has been confronting the Jaishul Adl Sunni rebels.

Last month the group announced it had executed one of the five, Jamshid Danayifar, and warned of more executions to come unless Iran freed Sunni prisoners. The Iranian authorities immediately denied the execution claim, insisting that all five soldiers were alive.

In mid-February, Iran warned that it could consider sending troops across the border in Pakistan to free the soldiers, and denounced what it called Islamabad’s inability to secure its own borders.

Border guards chief Hossein Zolfaghari has admitted that there was “negligence” in the lead-up to the kidnapping, saying those responsible were suspended, with some facing prosecution.

Jaishul Adl took up arms in 2012 to fight for what it says are the rights of Iran’s minority Sunni population.

Sistan-Baluchestan, which is home to a large Sunni minority, has been the scene of unrest in recent years fuelled by its alleged marginalisation by the predominantly Shiite Islamic republic.

Jaish-ul Adl, whose name in Arabic means “Army of Justice,” has claimed several attacks against Iranians in the region. These include the assassination of a local prosecutor and the killing of 14 border guards in an ambush in 2013.

The border region is also rife with drug and arms traffickers.

Also in March, Iran’s President Hassan Rouhani phoned Pakistan’s Prime Minister Muhammad Nawaz Sharif asking for “serious action” to free the guards.

The case sparked outrage in Iran and inflamed tension between Iran and Pakistan, where the abducted guards were apparently held.

A massive social media campaign was launched in Iran on behalf of the five abductees.

Militant faction, Jaishul Adl has been active in the borderlands between predominantly Shiite Iran and Pakistan, home to a Sunni majority and Shiite minority. Iran calls Jaishul Adl a terrorist organization and says it operates from sanctuaries in Pakistan’s Baluchistan region.