A 30-year-old man has been arrested on suspicion of GBH after an assault forced the temporary closure of Boston Central Park, which has since reopened to the public.
A man in his 40s suffered serious injuries and was taken to hospital after the incident, which was reported to Lincolnshire Police at around 5pm on Sunday, March 28.
Police said on Tuesday that the arrested man remains in custody and will be questioned in due course. The victim remains in hospital.
A member of police forensic staff in a white boiler suit was seen walking around the park with two other people while it was cordoned off. The park has now reopened to the public.
Police are continuing to appeal for witnesses and anyone with information should contact them on 101 quoting incident number 428 of March 28.