The protesters were reacting to reports of an apparent desecration of the Muslim holy book.

On its Facebook page, the extreme right group Danske Patrioter posted on Friday video of a man burning what seemed to be a Koran and trampling an Iraqi flag.

Copenhagen Police deputy chief, Trine Fisker, told AFP that "not more than a handful" of protesters had gathered Friday across from the Iraqi embassy.

"I can also confirm there was a book burnt. We do not know which book it was," she said. "It was quite peaceful."

In central Baghdad, the protesters gathered in the pre-dawn darkness after midnight at Tahrir Square.

"Yes, yes to the Koran!" shouted the protesters, mostly young men.

Some carried portraits of Sadr, who has a following of millions among the country's majority Shiite population and wields great influence over national politics.

Security forces cut two bridges leading to the high-security Green Zone where governmental institutions and foreign embassies are located.

The demonstrators tried to force their way through before officers pushed them back and the protesters eventually dispersed several hours later, after scuffles erupted, an interior ministry official told AFP, speaking anonymously because he was not allowed to brief the media.

Protesters were trying to reach the embassy of Denmark, the official said.

Early Saturday Iraq's foreign ministry had condemned "the desecration of the holy Koran and the Iraqi flag in front of the embassy of Iraq in Denmark."

The ministry's statement said that "these actions provoke reactions and put all the parties in delicate situations."

A separate statement said "we cannot allow to happen again" what occurred at the Swedish embassy.

It reaffirmed Baghdad's "full commitment" to the Vienna Convention on Diplomatic Relations and said it guarantees "the protection and security provided to diplomatic teams".

Hundreds of Sadr supporters were behind the storming and burning of Sweden's embassy in Baghdad early Thursday, over a planned burning of the Muslim holy book in Sweden, weeks after the same protester there lit pages of the Koran.

The actions of Sweden-based Iraqi refugee Salwan Momika triggered condemnation across the Muslim world.

Iraq condemned the attack on Sweden's embassy but expelled Stockholm's ambassador.

Swedish Foreign Minister Tobias Billstrom called Momika's protest "a clear provocation" that "in no way reflects the Swedish government's opinions", while also stressing a "constitutional right to freedom of assembly, freedom of expression and freedom to demonstrate".