Transcript for 4 men arrested on suspicion of plotting UK terror attack

Six days before Christmas eight terror plot foiled. British police tell ABC news they've arrested for men between the ages of 21 and 41 who are plotting an attack on a Christmas target. Early Tuesday morning to bomb squad showed up at one address in west Yorkshire police say the attack plans were in advanced stages. It spent eight deadly year in the UK and since March security officials believed they boarded at least ten implement attacks. About threats is multi dimensional. Evolving rapidly. And operating a to scale and pace we've not seen before. It Director General of MI five's that intelligence services are racing to keep up. It's at the highest tempo I've seen in my 34 yet Korea. Today there is more terrorist activity. Coming out to us more quickly. And it can be harder to detect. And exactly one years since the drilling Christmas market truck attack. Twelve dead and nearly 100 injured many in life changing ways. Under heavy security today German Chancellor Angela Merkel marked the anniversary. I'm insulate today is a day of Greece she says and also do you things better than the past. In Germany that Christmas market will remain closed all day out of respect for the Vick yet here in the UK only for today across Europe actually at the holidays approach. Authorities are outpacing the theme that fit challenge how to make her nothing and wind slip through the cracks. Molly and Terry ABC news lend it.

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