Up to 12 Iranians who were kidnapped in Syria months ago have been released, Iranian media reported on Thursday. Iran's official IRNA news agency said: "Informed sources in Syria say 12 Iranian nationals have been released, seven of whom are of Iranian pilgrims and five are Iranian engineers." Another outlet, Press TV, mentioned only the release of five engineers without giving a source for its report. Those five were said by Iranian officials to have been engineers working on an electricity plant near the flashpoint city of Homs for Iran's Power Plant Projects Management Company, or Mapna, when they were taken in late December. Previous reports said a total of seven Iranian engineers had been abducted near Homs - five initially, then two others who had gone to search for them. Iran in February said the seven had been freed, before correcting the information and saying they remained captives. An unknown group calling itself the "Movement Against the Expansion of Shia [Theology] in Syria" claimed responsibility for the Iranians' abduction in a statement received by AFP in Nicosia at the beginning of January. The rebel Free Syrian Army later said it was holding five Iranian Revolutionary Guards abducted in Homs, but it was not clear if it was referring to the "engineers" or to a different group of Iranians. In addition, 22 Iranian pilgrims travelling to holy Shia sites in Syria were reported to have been kidnapped since late December. Half of them were released in early February. IRNA's report suggested that most of the remainder were now also freed. Syria, Iran's principal ally in the Middle East, is roiled by a year-long uprising that has seen more than 9,000 people killed, according to UN estimates. Rebels accuse Iran of helping Syrian authorities in their deadly crackdown.