COLLEYVILLE, Texas—A rabbi who was among four people held hostage at a Texas synagogue said Sunday that their armed captor grew “increasingly belligerent and threatening” toward the end of the 10-hour standoff, which ended with an FBI SWAT team rushing into the building and the captor’s death. Authorities identified the hostage-taker as a 44-year-old British national, Malik Faisal Akram, who was killed Saturday night after the last hostages ran out of Congregation Beth Israel around 9 p.m. The FBI said there was no indication that anyone else was involved. The investigation stretched to England, where late Sunday police in Manchester announced that two teenagers were in custody in connection with the standoff. Greater Manchester Police tweeted that counter-terrorism officers had made the arrests but did not say whether the pair faced any charges. Katie Chaumont, a spokeswoman for the FBI in Dallas, referred questions to police in Manchester. President Joe …