<p>LONDON — Britons bracing for a terror attack like last month's Madrid train bombings are coming to terms with the idea the attackers may not be foreign militants but the sons of friendly Asian families living next door.</p>
<p>Police yesterday were questioning eight young British-born Pakistanis arrested a day earlier in raids that officials said had foiled a major bomb plot. Half a ton of ammonium nitrate, a fertilizer suitable for making bombs, was seized.</p>