ISIS challenges Prince Harry to a fight

The man identifying himself as Abu Uqayl, appeared in a three-and-a-half minute video in which he encourages would-be terrorists to fight for ISIS in Asia, the Middle East and Africa.

"To Harry, you come to Singapore and tell such stories to gain sympathy for the London terror attacks. Why don't you come here and fight us if you're man enough, so that we can send you and your Apaches (helicopters) to hellfire," says Uqayl in the video.

The reference is to the fact that the 33-year-old prince flew Apache attack helicopters in Afghanistan when he served as a soldier in the British Army in the past.

The fifth in line to the British throne had visited Singapore soon after an ISIS-claimed terror attack in London in June during which three knifemen had used a van to ram pedestrians on London Bridge before stabbing people in restaurants and pubs around Borough Market area of London.

In his speech, Harry had made a reference to the attack, which had claimed eight lives and injured 48 others.

Singaporean authorities have identified the man in the video as 39-year-old Megat Shahdan bin Abdul Samad, who left the city-state to work in the Middle East in 2014.

"Our security agencies have been aware for some time now of the presence in Syria of a Singaporean, Megat Shahdan bin Abdul Samad, 39, and have been monitoring his activities," the country's Ministry of Home Affairs said in a statement.

"It is believed that the person in the video calling himself 'Abu Uqayl' is Shahdan."

Prince Harry is currently in Toronto, Canada, at the Invictus Games – a sporting event he founded for injured war veterans.