Seven Iranian engineers who were abducted in the Syrian city of Homs last December have been released, local satellite Press TV reported on Friday.

An informed source with the Iranian Energy Ministry confirmed on Friday the release of the seven engineers, said the report.

Five of the seven freed Iranians were kidnapped by unknown armed gunmen on their way to the 450-MW power plant in the troubled Syrian city of Homs on December 21.

The technicians have been building the city's Jandar power plant for the past two years.

The two others were abducted one day later while they were on a mission to discover the whereabouts of their missing colleagues, said Press TV.

According to the report, Iranian engineers and experts are currently implementing development projects in Syria, valued at more than 1.7 billion U.S. dollars.

Iran's Foreign Ministry spokesman Ramin Mehmanparast confirmed on Tuesday the release of other 11 Iranians abducted earlier this month in Syria.

The spokesman said that 11 abducted Iranian pilgrims were released by the help of "friendly countries."

Earlier on Tuesday, local Mehr news agency reported that the kidnapped Iranian pilgrims were freed by the help of Turkey, after they were abducted on a road connecting the Syrian city of Hama to the capital Damascus on February 1.

There have been a string of kidnappings of Iranian citizens over the past several months in Syria. On January 26, a group of unidentified armed men stopped a bus carrying Iranian pilgrims on a road from Damascus to the northwestern city of Aleppo, abducting 11 Iranian men.