<p><br /> A man who claimed voices told him to kill a pregnant 21-year-old as she walked to work has been jailed for life.<br /> </p><p><br /> Alan McMullan, 54, fatally stabbed Claire Wilson in the street as she walked to her job as a Pizza Hut waitress in Grimsby, North East Lincolnshire, on June 7 last year.<br /> </p><p><br /> McMullan denied murdering Miss Wilson, who was six months pregnant, on the grounds of diminished responsibility but a jury at Hull Crown Court took just 90 minutes to convict him on Wednesday.<br /> </p><p><br /> Judge Michael Mettyear said it was possible McMullan would never be released from jail and he stressed it would be a matter for the Parole Board to consider. However he did say McMullan must serve a minimum of 20 years in prison.<br /> </p><p><br /> In court the killings were described as "senseless and unnecessary."<br /> </p><p><br /> The judge said he had read of the "terrible struggle" the family had to endure following the murder. He said it was another example of a knife attack which rightly causes worry and concern in the community.<br /> </p>