Police are searching for vandals who have plastered areas of Sincil Bank and Carholme Road with garish graffiti tags.
Businesses and a Lincoln school are among those who have been targeted by the large scrawled markings, which are similar in style using green and black paint.
One business on St Andrews Street was covered in the mark as well as St. Peter at Gowts school.
Lincolnshire Police officers are asking for anyone with information to get in touch by calling 101.
People can also report anonymously via Crimestoppers on 0800 555 111.