Police in Hamilton say they have concerns over items of sportswear and a racing bike found near the Waikato River.
A 10-speed bike was found along with a helmet, watch and running shoes in Memorial Park by council parks staff on Tuesday.
Police say they can not discount the possibility a triathlete may have gone into the river for a swim and may be missing.
However, they say no one has been reported missing and any information from the public would help.
