The mother of Austin Tice, the American journalist abducted in Syria in 2012, told reporters Friday that her son is believed to be alive and is being "treated well," without providing further details.

"We have from a significant source that has already been vetted all over our government, Austin Tice is alive, Austin Tice is treated well," Debra Tice, surrounded by family members, told a news conference in Washington.

"We want to be very careful about what we share. He is being cared for and he is well, we do know that," she added.

Abu Mohammed al-Jolani, leader of the Islamist rebel alliance that has captured swathes of Syria in a lightning offensive, is an extremist who has adopted a more moderate posture to try achieve his goals.

At the head of Hayat Tahrir al-Sham (HTS), which is rooted in Syria's branch of Al-Qaeda, Jolani says the goal of his offensive is to overthrow President Bashar al-Assad's rule.

Initiated into the thousand-year-old practice of Nablus soap making by a distant relative, Umm al-Abed is now passing on the secrets of the practice newly designated by UNESCO as intangible world heritage.

Umm al-Abed handcrafts soap at her home in the village of Salem, east of Nablus, in one of many small soap workshops across the Israeli-occupied West Bank.

The process is rudimentary, involving a plastic bucket in a concrete courtyard and just three ingredients: olive oil, water and lye.

Like many others in the Syrian capital Damascus, student Shadi chose to stay home so he could keep up with the pace of events since rebels launched a shock offensive last week.

"I had no wish to go out and everyone chose to stay in to follow the news surrounded by their loved ones," said Shadi, who did not wish to give his full name.

As the rebels have taken city after city in quick succession, many Syrians have been wracked by uncertainty, fearing a revival of the worst days of Syria's grinding civil war now in its 14th year.

Wafaa Omar spent eight months in a Syrian jail in 2014 before being released. The English teacher has lived in Istanbul ever since but is desperate to return to Damascus.

"From one week ago, I feel a very beautiful feeling. Yesterday I was crying and crying and crying," she told AFP, convinced that the advance of Syrian rebels will lead to a political solution before they reach the capital.

The image is particularly symbolic: A statue of former President Hafez al-Assad, the father of Syria's current ruler Bashar, was toppled in Hama after Islamist-led rebels overran the country's fourth-largest city, video authenticated by AFP showed.

A machine's long mechanical arm tipped the towering statue over to cheers and cries of "Allahu Akbar" (God is Greatest) and "Thank God" from the crowd, along with a deafening sound of celebratory gunfire, the night-time footage published Thursday night on social media showed.

Iran plans a major increase in the production rate of highly enriched uranium, the UN nuclear watchdog said Friday in a confidential report seen by AFP.

An updated design of Iran's Fordo plant showed that the effect of the change "would be to significantly increase the rate of production of uranium enriched up to 60 percent", the International Atomic Energy Agency (IAEA) report said.

Production will jump to more than 34 kilogrammes of highly enriched uranium per month, compared to 4.7 kilogrammes previously, added the report to the IAEA's board of governors.

Iraqi Prime Minister Mohammed Shia al-Sudani on Friday said his country was pressing diplomatic efforts aimed at "containing the crisis in Syria due to its clear impact on Iraqi security".

His remarks came ahead of a meeting between the top diplomats of Baghdad, Damascus and Tehran to discuss developments in Syria, which has been in the throes of a shock offensive that has seen rebel forces capture key cities from the government.

At a church in Syria's Aleppo, Christian worshippers attended mass days after their city came under the control of Islamist-led rebel forces who have sought to allay residents' concerns over their nascent rule.

"Despite the circumstances in Aleppo, we made sure to celebrate Saint Barbara's feast as we do every year," said 60-year-old Therese Kalaghasi.

"We pray for peace in our country," she said during mass at the Armenian Catholic Saint Barbara Church in the predominantly Christian district of Sulamaniyeh.

Gaza's civil defence agency Friday reported deadly air strikes around Kamal Adwan Hospital in the territory's north as well as "direct fire" on the health facility, which the Israeli army firmly denied.

Several witnesses described intense bombings in the vicinity of the hospital.

"There was a series of air strikes on the northern and western sides of the hospital, accompanied by intense and direct fire," said hospital director Hossam Abu Safieh, adding that four staff were killed.