Family, friends and members of the community gathered to remember the little boy who was found on Monday afternoon, 48 hours after he went missing.

The family has requested that his name not be released and has asked for privacy during this difficult time.

UPDATE MONDAY 7pm: The Bendigo Advertiser believes the boy's body was found by local fishermen, who alerted authorities.

UPDATE MONDAY 3pm: Police have located the body of a six-year-old boy who went missing in the Murray River at Koondrook on Saturday.

Police from Deniliquin Local Area Command found the boy’s body about 7.5km north of the campsite on Gunbower Island at 2pm today.

The boy has been formally identified.

An investigation into the circumstances surrounding the incident is under way and a report will be prepared for the Coroner.

UPDATE MONDAY 11.30AM: The search for a six-year-old boy who was swept down the Murray River in Victoria's north resumed at dawn on Monday, as police all but gave up hope of finding the child alive.

The young boy disappeared while swimming in the river at a campsite on Gunbower Island Reserve, near the border town of Koondrook, on Saturday afternoon.

Police divers returned to the water on Monday, but Chief Inspector Michael Tranby said their operation had become a recovery one.

"We have no doubts that he has passed away as a result of going into the water," Chief Inspector Tranby said.

"We are keeping in mind the nature of the river and what happens if you are not found within that 24-hour period."

SUNDAY 9.12PM: POLICE have no doubt a six-year-old Bendigo boy has died after being pulled under water when swimming in the Murray River at the weekend.

The boy is missing after almost two days of searching conducted by NSW and Victorian police and NSW SES.

Inspector Tranby said because of the nature of the Murray River the possibility of finding the boy alive was unlikely.

"We have got no doubts that he has passed away as a result of going into the water," he said.

"It is a recovery mission now.

"At this point we are looking at continuing the search until we reassess at midday.

"We are keeping in mind the nature of the river and what happens if (he is) not found within that 24-hour period."

SUNDAY 8.30PM: NSW Police will remain at the site overnight.

Chief Inspector Michael Tranby said the search was now a recovery mission.

"We have no doubts that he has passed away as a result of going into the water," he said.

"We are keeping in mind the nature of the river and what happens if you are not found within that 24-hour period."

SUNDAY 5.30PM: Police and SES will tomorrow continue their recovery mission for a missing Bendigo boy with little hope he will be found alive.

The six-year-old boy was pulled under water by heavy currents, police say.

The recovery mission will resume at 8am tomorrow in the Gunbower Island Reserve near Koondrook.

SUNDAY 11.30am: Police have confirmed a six-year-old boy was with two Bendigo families camping on the Murray River when he was swept under the water and disappeared.

Police were called to a campsite on Gunbower Island near Koondrook about 2.30pm on Saturday after a six-year-old boy disappeared while swimming.

Chief Inspector Michael Tranby, the Deniliquin local area commander, said the boy had been swimming with six other children when they started to drift downstream.

"There were two families from Bendigo in Victoria that were camping in Gunbower Island forest at Koondrook, just on the Victorian side of the border on the Murray River," he said.

"Between them, there were seven children with the two families.

"They got in trouble with the current and four swam to the bank. The three others were struggling and adults entered the water and were able to rescue two of them, but a six-year-old boy went under the water and he did not resurface."

NSW and Victoria police, NSW SES, other emergency services and members of the public immediately started searching for the boy.

"Divers from NSW, with our luck, were at Wagga at the time and they came across from Wagga to Barham and they commenced a search of the water about 9pm last night," Chief Inspector Michael Tranby said.

"The emergency services searched until about 10.30pm last night, when it was suspended.

"We recommenced a search this morning at 8am with SES and police divers searching both in the water and along the banks."

Koondrook Caravan Park owner John Forbes estimated there were a few thousand holidaymakers at Gunbower Island.

"It's an island that's 50 kilometres long; it's the biggest inland island in Australia," he said.

"The water's always moving pretty fast because it is the Murray. The thing is, if you're going to swim in the Murray you've got to have adults there with you."

Gunbower Caravan Park owner Kim Nelson said she didn't allow her children to swim in the Murray without a life jacket.

"The current is quite strong," she said.

"You've got to know the Murray.

"My kids have been brought up on the Murray; we'd holiday here every year before we bought the caravan park, and they weren't allowed in that Murray River without a life jacket.

"That was the camp rules ... they had to sit there if they didn't have a life jacket on.

"It's unpredictable because if you swim out that little bit too far, like kids do, it can get you. The current can get you."

EARLIER: A search for a six-year-old boy who was swept down the Murray River will resume on Sunday morning after poor visibility forced police to call off efforts overnight.

Emergency services were called to a campsite on Gunbower Island in Koondrook between Echuca and Swan Hill just before 2.30pm where boy was swimming at a family gathering, a NSW police spokesman said. 

The boy had been swimming in the Murray River with six other children when they began drifting downstream. 

Four of the children were able to get out of the water, but three of the children were caught in the current. 

Family members and onlookers dove into the river and were able to retrieve two of the three children from the water, but the six-year-old could not be found. 

A search by NSW and Victorian police, divers, SES and volunteers continued until around 10.30pm on Saturday when poor light forced it to be called off.

The search was due to resume from about 8am on Sunday, police said.