Transcript for Bombs apparently mailed from Ireland company: London authorities

Now, to the terror scare in London at this hour, after three explosive packages, one containing a small improvised explosive device, caught fire at heathrow airport, and within hours, those two other packages were found at other locations. There is a manhunt under way this evening, and here's our senior foreign correspondent Ian Pannell now. Reporter: Tonight, the hunt is on for the London bomber. After three small improvised explosive devices were sent through the mail. Delivered to two of London's airports and one to the city's Waterloo railway station. It was here, near heathrow airport, where someone started to open one of the letter bombs, causing it to ignite. The building had to be evacuated, but no one was injured. Officers from counterterrorism command have now launched an investigation. London's metropolitan police tweeting, "We're treating the incidents as a linked series." Perhaps one clue -- each package appeared to have been mailed from a bus company in Dublin, Ireland. Irish police now also helping. Opportunity, counterterrorism warning people here at Waterloo and elsewhere to be alert to further suspicious devices. Meanwhile, the hunt goes on for who mailed these packages, and most importantly, why. David? Ian Pannell, thank you. And of course, we are just

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