British police are facing criticism for failing to arrest a man draped in a flag of the Islamic State group near the Houses of Parliament in London on Sunday. The man, whose identity is not yet known, was also carrying on his shoulders a small child waving a similar flag, according to photos shared on social media.

“This man was spoken to by officers, with consideration given to relevant legislation, particularly the Public Order Act, and the decision was taken by officers at the time that the man was acting within the law,” a police spokesman reportedly said. “While support of and membership of ISIS is unlawful it is not a criminal offence to advocate the creation of an independent state. … Wearing, carrying or displaying of an emblem or flag, by itself, is not an offence.”

The man was spotted by a tourist and his photos were initially shared on a Korean web forum, according to media reports.

The incident, which has sparked widespread outrage among several social media users, came just two days before the 10-year anniversary of the July 7 suicide bomb attacks in central London. Over 50 people were killed and hundreds of others were injured in the incident -- labeled one of the worst series of coordinated terror attacks in the country.

The incident also comes just days after the Guardian reported that two of the three east London schoolgirls who had fled to join ISIS in Syria in February are now married to men approved for them by the militant group.  

ISIS, which currently controls territories in Iraq and Syria, is believed to have over 20,000 foreign fighters in its ranks. Of these, at least 600 are British nationals, according to an earlier estimate by the British government.