Militants fighting for the Islamic State have reportedly destroyed a famous statue of a lion in the captured city of Palmyra - despite promising locals they would not obliterate the ancient city.

Following their capture of Palmyra last Thursday, ISIS militants are understood to have won the support of much of the local population by promising not to destroy the city's famous monuments.

But it appears that promise was too much for the jihadis to keep, with eyewitnesses claiming they destruction of millenia-old Statues and buildings is already very much under way, with the most significant loss so far being the celebrated Lion of Al-Lat, which dates back to the first century AD.

Destroyed: The 1,900-year-old Lion of Al-Lat statue (pictured before ISIS seized Palmyra) is said to have been destroyed by the terrorists. The celebrated monument was built as a tribute to a pre-Islamic Arab goddess

Takeover: ISIS has raised its flag over ancient buildings in Palmyra while also slaughtering hundreds of locals - including women and children

Chilling: Thick black smoke rising over Roman ruins that have stood for thousands of years in the central Syrian desert city. Following their capture of Palmyra last Thursday, ISIS militants are understood to have won the support of much of the local population by promising not to destroy the city's famous monuments

On guard: Heavily armed jihadis can be seen patrolling the steps of Palmyra's ancient amphitheatre

The lion statue was destroyed by ISIS militants on Saturday, according to the International Business Time, who quoted eyewitnesses on the ground in Palmyra.

'I heard a loud noise, so I went up to the roof to see what is going on,' one local man said.

'I saw Daash crushing the 'god lion' statue with construction machines. There were many other crushed statues but I could not recognise the rest of them because they were totally ruined,' he added, using an Arabic acronym for the terror group.

The act of destroying the statue came just days after ISIS gathered Palmyra's citizens together and publicly promised not to bulldoze the city's ancient buildings, as they previously did in Nimrod.

'As for the historical monuments, we will not touch it with our bulldozers as some tend to believe,' ISIS commander Abu Leith was quoted as saying on a local radio broadcast.

However the promise did come with a get-out clause, as the depraved fighters insisted they would 'pulverise' any statues they discovered in the city that the believed citizens secretly prayed to.

The interior of Palmyra's ancient Roman amphitheatre is seen in these pictures released by ISIS supporters

Destroyed: This photograph shows rubble in Palmyra's streets caused by Syrian regime airstrikes on ISIS

Frontline of fighting: The buildings are said to have been reduced to rubble by Syrian regime warplanes

The lion statue in Palmyra dates from the first century AD and stood outside the city's famous Temple of Bel.

The statue was dedicated to the pre-Islamic Arabian goddess Al-Lat, who was one of the three chief goddesses of Mecca along with Manat and al-Uzza.

The Temple of Bel itself was built in 32 AD - six hundred years before the arrival of Islam in Syria - and was dedicated to the Semitic god Bel - who was worshiped by Palmyra citizens along with the lunar god Aglibol and the sun god Yarhibol.

Since ISIS seized control of Palmyra, the temple and its surrounding area have been appropriated by ISIS militants, who are said to be using it as a military base.

Locals who preserved the site for the last 1,900 years are now said to be banned from entering the area unless the are willing to sign up to become ISIS jihadis.

Rubble: Debris from badly damaged and destroyed ancient buildings are seen littering the streets of Palmyra

ISIS is accused of executing hundreds of people in and around Palmyra since it swept into the oasis city last week after a lightning advance across the desert from its stronghold in the Euphrates Valley to the east.

But they have also released propaganda images showing the terrorists releasing prisoners from Tadmor Prison - with the convicts seen embracing one another in the streets after being freed.

Yesterday the extremists 'called people to watch' as they executed 20 local men in a Roman ampitheatre in the ancient Syrian city.

The men were shot dead in the restored ruin, which had been used for an annual festival in the city, in front of the crowd. The murdered locals were accused of being government supporters, according to a report from the Syrian Observatory for Human Rights.

'IS executed 20 men by firing on them in front of a crowd gathered in Palmyra's Roman theatre, after accusing them of fighting for the Syrian regime,' Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, told AFP.

He added: 'IS gathered a lot of people there on purpose, to show their force on the ground.'

Under threat: Many of the ancient Roman buildings in Palmyra have been standing for thousands of years

Chilling: The short video released by the local pro-ISIS media company Aamaq News shows thick black smoke rising over Roman ruins that have stood for thousands of years in the central Syrian desert city

Sickening: A picture sent by activists to a Western journalist shows a row of men lying in pools of blood in a street in Palmyra last week. At least four of the men had been decapitated

This morning the European Union added a high-ranking Syrian military official to its sanctions list, as it extended measures against supporters of President Bashar al-Assad for another year.

The EU began imposing asset freezes and travel bans on Assad and his supporters in 2011 to protest a government crackdown on Assad's opponents. With Syria's civil war now in its fifth year, the sanctions list has grown to more than 200 people and 70 organisations.

EU governments decided to extend the sanctions another year and add one person to the list - a high-ranking military official the EU accused of being 'responsible for repression and violence against the civilian population in Damascus and Damascus countryside.'

The name of the official, who will be subject to an asset freeze and ban on travelling to the EU, will not be made public until details of the sanctions are published in the EU's Official Journal on Friday.

Other EU sanctions on Syria include restrictions on exporting equipment that might be used for internal repression and a ban on importing oil from Syria.