UK police arrest 2 more men in counter-terrorism investigation

(CNN) -- UK police arrested two more men Friday in connection with an investigation into suspected membership of a banned organization.

It comes a day after nine men were arrested in London on terrorism charges, one of them named in British media reports as radical British cleric Anjem Choudary.

The two latest arrests came in the early hours in a swoop on a vehicle traveling on the M6 motorway, which runs northwest from the English Midlands to Manchester and beyond.

One suspect, aged 33, was arrested on suspicion of being a member of a banned organization, supporting a banned organization and encouraging terrorism, London's Metropolitan Police said in a statement.

The second man, aged 42, was arrested on suspicion of assisting an offender.

Both remain in custody at a central London police station.

The nine men arrested Thursday, ages 22 to 51, also remain in custody in London, police said. Searches continue at a number of addresses.

"These arrests and searches are part of an ongoing investigation into Islamist related terrorism and are not in response to any immediate public safety risk," the police statement said.

Radical cleric

Anjem Choudary, who was a co-founder of the banned UK Islamist group Al Muhajiroun, told CNN last month that the world had been split into two camps.

There's a "camp which believes that sovereignty and supremacy belongs to God. They are the Islamic State, at the head of which is Abu Bakr al-Baghdadi," Choudary said. "In the other camp you have those people who believe sovereignty and supremacy belongs to man. At the head of that camp is Barack Obama."

"I believe this Islamic State will spread, rapidly, and I believe it will be in Europe and even America within decades."

Police have not named the suspects or the banned organization concerned.

Cameron lays out plans to counter UK jihadi threat

Terror threat level raised

The Home Office has listed 60 international proscribed terrorist organizations as of August 2014.

They include networks such as ISIS and al Qaeda, as well as UK-based groups such as Al Muhajiroun, which emerged in 1996 and has operated under a range of other names since being disbanded in 2004 and banned in 2010.

The UK Home Office last month raised its terror threat level from "substantial" to "severe."

The government also announced new measures to combat the threat from Islamist extremism, including a radical new measure to ban Britons from coming home once they join jihadi ranks abroad.

UK authorities estimate that 500 Britons have gone to Syria and Iraq to fight with Islamist groups.