New Scotland Yard
New Scotland YardReuters

Britain's most senior police officer revealed shocking statistics on Tuesday, according to which five UK citizens are leaving each and every week to join the brutal Islamic State (IS or ISIS) terrorist group in Syria and Iraq.

Metropolitan Police Commissioner Sir Bernard Hogan-Howe was quoted by the Huffington Post saying: "the advance of IS across Iraq and Syria...are not just the horrors of distant lands. We know that over 500 British nationals traveled to join the conflict. Many have returned and many will wish to do so in the coming months and perhaps in future years."

"We still have an average of five people joining them a week," said Hogan-Howe. "Five a week doesn't sound much but when you realize there are 50 weeks in a year, 250 more would be 50% more than we think have gone already."

And that's the best case scenario, warned the police commissioner.

"Those numbers are a minimum. Those are the ones that we believe have gone," he noted. "There may be many more who set out to travel to another country and meandered over to Syria and Iraq in a way that is not always possible to spot when you have failed states and leaky borders."

Hogan-Howe warned of the great danger that jihadists may return to commit terror in England, saying "the drumbeat of terrorism in the UK has changed. It's faster and it's more intense."

That danger was illustrated earlier this month, when a four-man ISIS terror cell was busted by police before apparently planning to behead one or several Britons on the streets of London.

He added that the Metropolitan Police have been active in confronting the threat, making 218 arrests over terrorist-related activities since the start of the year - the figure marks a 70% increase compared to three years ago.

The commissioner added that a special police unit is actively engaging the recruitment war ISIS is waging online, removing over 1,000 pieces of illegal content such as videos of ISIS beheadings from the internet each week.

Ironically, the UK's National Union of Students (NUS) - which has voted to boycott Israel - last week rejected a motion condemning ISIS on the grounds that it could be considered "Islamophobic."

While the figures for the UK look bleak, the ISIS recruits from Britain are a mere pittance compared to France, where over 1,000 citizens are predicted to have joined ISIS. Shockingly enough, those recruits include several Jewish girls who apparently converted to Islam.