The Lebanese Hezbollah party has recently set up a new secret prison in Syria, revealed the Syrian Observatory for Human Rights.
Director of the UK-based monitor Rami Abdul Rahman said the facility was set up west of Palmyra city in Homs' eastern countryside in central Syria.
He told Asharq Al-Awsat this was not the first such prison set up by the Iran-backed party.
It had established such prisons in the Qalamoun region, including one in al-Qusayr city near the Lebanese-Syrian border.
The facility is overseen by Hezbollah loyalists recruited from among the local population.
Fighters combating Hezbollah and detained in regions controlled by the party are held at these prisons, said Abdul Rahman.
The party refuses to turn them over to the regime, contrary to previous occasions when detainees were released in exchange for money.