Syria is home to many ancient ruins, including the Temple of Bel on the site of ancient Palmyra. Many archaeological sites have suffered damage amid civil war as well as looting by the Islamic State. (AP)

Almost 100 Syrian artifacts looted by the Islamic State have been smuggled into Britain and sold to raise money for the extremist group’s activities, art crime experts and archaeologists have warned, according to British news organizations.

The items, allegedly being sold in London, include gold and silver Byzantine coins as well as Roman pottery and glass worth hundreds of thousands of dollars, the Times newspaper reported Wednesday.

The London paper compared the phenomenon with Africa’s “blood diamond” industry, in which money raised by the sale of African diamonds financed wars and conflicts across the continent.

“I get approached all the time about looted artifacts, whether it’s directly from someone who’s trying to sell it or images that were sent to somebody who has offered to buy it,” Christopher Marinello, director of Art Recovery International, told the Times. His group specializes in the identification and recovery of stolen and disputed art and antiquities.

A tourist looks at the ruins of the Citadel in Aleppo in Syria. (Kaveh Kazemi/GETTY IMAGES)

Marinello said one item alone could be worth tens of thousands of dollars, but the more valuable and unique the item, the more scrutiny there will be, and so collectors tended to shy away from more valuable items. He said the trade then tended to be in “middle-value objects that don’t stand out.”

The newspaper also quoted Michael Danti, an archaeologist with the Syrian Heritage Initiative, as saying that the Islamic State was known to be involved.

“We see heavy looting in ISIS-controlled areas,” Danti was quoted as saying, using another acronym for the militant group. “Also, common sense: ISIS controls smuggling.”

The smuggling is thought to take place via Turkey, Jordan and Lebanon, the Times reported, routes also known for smuggling people, guns and drugs.

BBC’s Radio 4 also took David Gill, professor of archaeological heritage at University Campus Suffolk, to unnamed London galleries to find out whether he could spot any looted artifacts.

“We went into one gallery and were chatting about a piece and the person quite openly said, ‘We just got this out of Syria,’ and we sort of looked at each other and said that’s really quite interesting, and he said, ‘Oh, well, this piece is more interesting. It has just come from Iraq,’ ” the archaeologist told Radio 4. “So it’s quite open in that sense.”

Robert Jenrick, a member of Parliament and former director of the auction house Christie’s, called the trade “the greatest threat to culture since the end of the Second World War and also, more pressingly, a major source of revenue to ISIS and the Assad regime,” the Times reported. Syrian President Bashar al-Assad has been battling a rebellion since 2011.

Jenrick said, however, that such looted artifacts had not appeared on the open market yet.

A spokeswoman for the Metropolitan Police told the newspaper that police had “four live investigations, all of which require liaison with foreign jurisdictions,” into the matter. She said no arrests had been made, however.