Transcript for London terror attack: Surveillance of 18-year-old suspect
new developments after that terror attack on a London subway. Look at this tonight. New surveillance of an 18-year-old now in custody, seen carrying a bag, much like the one found on that train. And tonight, the British couple who took him into their home as a refugee. That family had been honored by the queen for taking in refugees. ABC's chief foreign correspondent Terry Moran from London tonight. Reporter: Caught on a security camera. Just a glimpse of a young man, but look at that white bag he's carrying. 90 minutes later, in that subway car, there's the smoking remnants of the botched parsons green bombing in a white bag. The 18-year-old suspect under arrest, seen here on a second security camera, hasn't been named by police, but ABC news has learned he is an Iraqi refugee who came to the U.K. Three years ago after his parents died. Today, investigators were swarming over the row house in suburban London where the suspect lived for a time. The home's owners, Penelope and Ronald Jones, once honored by the queen because they had served as foster parents for more than 200 kids over the years. Including the second suspect, arrested this weekend in west London, believed to be 21-year-old yahyah farroukh, a Syrian refugee. A neighbor says there'd been increasing police activity at that house before the attack. The last couple of times they dressed in black. No police cars. It was all -- it looked like it was all undercover, secret service kind of stuff. Reporter: Police were also searching the home where farroukh was living, just yards from the runway at heathrow airport. Police say the bomb was made cheap and deadly, but so unstable, terrorists have dubbed it the mother of Satan. David?
This transcript has been automatically generated and may not be 100% accurate.