a moment of profound pain. as the people who were trapped, terrified, try to come to terms with what happened, synagogues across the country have increased security in fear of copycat attacks. this was an act of terror. we're not going to tolerate this. we have this capacity to deal with assaults on, particularly the anti—semitism that has grown up. and so i'll be talking with... i put a call into the rabbi. we missed one another on the way up here. but they should rest assured that we are focused. as soon as it became known that akram was a british citizen, the investigation became global. counter—terror police in manchester are assisting the us authorities and are now questioning two teenagers who were arrested in the city last night. sophie long, bbc news, dallas. our correspondent, danny savage, is in blackburn.