The fishing line, which was tied at neck height, was found by a Police Community Support Officer (PCSO) out on patrol in Coningsby.
PCSO Alison Evans, who found the line across the footpath, said someone could have been seriously injured.
Anyone with information about the 30 October incident should contact police.
"Although I wasn't injured in any way, the footpath is regularly used by cyclists and had anyone cycling along there hit the line, it could have caused some really serious injuries," said PCSO Evans.
Pc Stuart Adams, from Lincolnshire Police, said: "What we do know is that if anyone had hit the fishing line at speed, the consequences could have been very serious and because of this, we need to trace those responsible as soon as possible."
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©
~RS~q~RS~~RS~z~RS~47~RS~)