A man on the run from police in Hamilton on Friday night was last seen in the Waikato River.
The 36-year-old was wanted in relation to a serious assault on a 26-year-old woman earlier in the evening, police said on Saturday.
They were called to an address on Montgomery Cres in Bader around 11pm, and saw him flee.
A police dog tracked him to the river at Cobham Bridge, near the city's gardens.
An hour later with the help of a helicopter they found him, but he disappeared from sight before they could reach him.
A search of the river is ongoing.