Jose Leiva/Sun Journal

A week after a group of Lewiston Middle School students painted over graffiti on a vacant building at 449 Sabattus St., vandals came back and spray-painted the wall. Lewiston police officer Bill Brochu, who worked with the school kids on the effort, plans to cover the new graffiti with fresh paint while police search for the culprits. “We will be investigating the matter and should we catch those responsible,” said police spokesman Lt. Mark Cornelio, “they will be prosecuted to the full extent of the law.” At noon on Saturday, police officer Tom Murphy will take another group of Lewiston Middle School students to paint over a year’s worth of graffiti on the sides of the old McCrory’s building between Park and Lisbon streets, as well as some buildings behind Victor News.