Tauranga's Mclaren Falls Park is closed this morning after one man was found dead there last night and another remains missing.
Searching stopped last night at about 11.15pm and McLaren Falls Park was cordoned off overnight.
The Police National Dive Squad has arrived from Wellington this morning, are being briefed and it is hoped they will resume searching for the second man by mid morning.
Police said the two men were seen going into the water around 5.20pm last night when they both disappeared from view.
The incident started when one of the men fell from a rope swing into the water. The other man then went in after him to help. The body of one of the men was recovered by police.
"He is believed to have drowned. The other person is still missing," a police statement issued last night said.
Trustpower TECT Rescue Helicopter pilot Liam Brettkelly said by the time the helicopter arrived on the scene at 6pm, with two experienced water rescue crew on board, one man's body had already been recovered.
Mr Brettkelly said he and his crew searched for about an hour without any sightings of the other missing man.
"Obviously there are shallow areas and deep areas but we had good vision of the search area, which was in the lower Lake McLaren, just up from the road bridge towards the net buoys and upwards for about half a kilometre.
"We had a pretty good look. It's quite likely the other man's body is hidden in a deep pocket or channel somewhere."
Mr Brettkelly said he understood the incident started when the rope a man was swinging from broke and he fell into the water, then the associate went in to try rescue him and also disappeared from view. It is understood one man may be a local, but police are yet to confirm the identities of the deceased and his missing associate.
Boats were also being used to search the area. The entrance to McLaren Falls was closed last night, and two men overlooked the canal at the end of the lake. Motorhomes were being turned away from the park.
Locals said it was the first drowning in the lake for at least 18 years and said it was extremely rare for people to get into difficulties while swimming there.
Two additional inflatable rescue boats were brought to the search area about 8pm and a large search and rescue vehicle arrived soon after.
A reporter at the scene said the lake level was being lowered to aid the search, which continued last night.
A group of six Indian students living locally gathered at the entrance to McLaren Falls Park after receiving a call informing them that two of their friends, also Indian nationals, had gone missing. Two other friends, who were at the park at the time of the drowning, were helping police with inquiries.
"It's a terrible tragedy," one said.