LONDON — The British counterterrorism police on Tuesday said Ann Widdecombe, a right-wing politician who was killed last week, had been the victim of a “targeted attack.”Widdecombe, 78, was found dead at her home in Haytor, in Devon, southwestern England, on Thursday, having sustained serious injuries.A 28-year-old white British man from Rotherham, a town in northern England around 270 miles away from the crime scene, was arrested on suspicion of murder on Saturday. On Monday, the police said they were also holding him “on suspicion of commission, preparation, or instigation of acts of terrorism.”In a briefing to the news media...