A former soldier scratched graffiti on a cell wall and threatened to blow up the Crown Prosecution Service.
Brian Cannell also wrote rude remarks about “the law.”
Cannell, 40, of Crystal Road, South Shore, pleaded guilty to causing damage.
He was given a 12-month conditional discharge and ordered to pay £100 compensation with £30 costs plus £15 victims’ surcharge by Blackpool magistrates.
Martine Connah, prosecuting, said Cannell was put in cell number 14 at Blackpool Central police station on March 2. At 9am the next morning a custody detention officer came to get him and spotted the damage which cost £150 to repair.
Cannell confessed he had done it because he was bored. Peter Cave, defending, said his client had served in the Army for five years but was now on benefits and suffering from depression.