The police dive squad has been called in after a man was seen dangling from a bridge over a river in Taupo.
Taupo police are concerned after the man was seen standing in a precarious position over the Waikato River this afternoon about 3.20pm.
A woman was driving past the Control Gate Bridge where the Thermal Explorer Highway meets Tongariro Street when she spotted the man.
"He was walking along a concrete structure over the water that can only be reached by climbing a fence and appeared to be gesticulating to himself," Taupo police said in a statement.
The woman was so concerned she drove by again, by which time he was sitting down.
She contacted police as another motorist.
Officers were very quickly on scene but there was no sign of the man.
Lake Taupo Coastguard carried out a preliminary search of the river and police carried out local area inquiries and checks of available CCTV in the area.
The police dive squad will search in the morning.
Police say the man may have left the area of his own accord.
"If that is the case, police would urge the man in question to make contact as soon as possible and provide assurance he is safe and well."
Police also want to hear from anyone who knows who this man might be, or anyone with concerns for the welfare of someone fitting his description: Maori, medium build, wearing a grey sweatshirt, light jean shorts and a hat. His age is unclear.
Anyone with information is asked to contact Taupo Police on 07 378 6060.