Frantic relatives of missing Lucas Dobson have told KentOnline of the horrifying moment the boy plunged into the River Stour.

His aunt Maciee Stanford, 18, said the youngster had fallen down a small gap between a jetty and a boat.

Her sister is Lucas's mum. Maciee, who is Deal Carnival Queen, said: "He was with his dad and his dad's friends along with other children.

"The incident happened because our Lucas was on the jetty and tried to step from there onto the boat but he fell in between the jetty and the boat.

"As soon as he fell, the three adults jumped in after but the current was too strong; he had already gone. In the short amount of time he could not be found.

"The current was so strong the three men could barely swim in it.

"They fish and do this regularly as it is behind one of the men’s houses - all the children play together here."

She said Lucas, who lives in Deal, could swim but the family feared the Warden House Primary School pupil would have been too scared to do anything.

Lucas's family joined the search for him as it resumed this morning, with crowds turning up to help.

Sgt Colin Millins speaks to volunteers

The public were being told to keep their search within 1km of Richborough Road.

In a statement, Kent Fire and Rescue said they had been inundated with offers of support.

It said: "A public briefing has taken place this morning to coordinate a plan enabling local people to help in the search for the missing 6-year-old boy.

"We’ve again been inundated with offers of support - Thank you. The emergency services need people to consider their safety and the risks associated with water. Unless you attended the briefing at Sandwich fire station and are aware of how you can help at this time, we would really encourage you to remain safe away from the area. We have a lot of help - thank you.

The long queue of volunteers

"A one mile exclusion zone has been set up on the river around the scrapyard at Richborough Road to prevent any form of public water vessel like canoes or boats with engines entering the primary search zone. This is to allow the water to remain as still as possible and to enable the search and rescue teams to carry out their work."

Teams search the river on Sunday morning

St Mary's Church made teas and coffees free of charge for volunteers and also made its toilets available for people to use.

It also had tables and chairs, where people were invited to take a rest in between the hard work.

The church said donations had been “incredibly generous”.

Ossie's Fish Bar was giving away food to volunteers.

Emergency services were called to Richborough Road in Sandwich at 1.20pm on Saturday following the accident involving six-year-old Lucas Dobson.

It is understood he fell into the River Stour during a family fishing trip. It is thought the boy's father dived into the river but was unable to reach him.

Scroll down for video

The search resumed at dawn.

Speaking at 9.40pm on Saturday a fire spokesman said: "The search for a missing six-year-old boy will continue until around 10pm tonight and will begin again in the morning.

"Emergency services have been working together to co-ordinate a search that takes in land, the river banks and along and in the water of the River Stour near Sandwich.

"The co-ordinated search by the emergency services, partner agencies and charities has involved specialist and experienced search and rescue teams.

"There has also been a large number of local people helping to do their bit in trying to find him.

"KFRS has over 30 members of staff at the scene from firefighters, the water rescue unit, technical rescue; who have been using the drone, and Buzz the KFRS search and rescue dog who is also part of the operation.

The search continued amid fading light

"The search has involved each agency working in zones to focus the co-ordinated efforts.

"Members of the public have also been allocated zones in the search."

Assistant director for Kent Fire and Rescue Service, Chris Colgan, said: "We're all incredibly grateful to everyone who has given everything today to try and locate this little boy.

"Our thoughts are with him and his family tonight at this very difficult and emotional time.

"I would like to appeal to people who have come to Sandwich to join the search - if you continue overnight please make sure your own life isn't placed at risk

"We have issued some safety advice about keeping clear of the river's edge, staying on the main tracks, working in groups and never alone and please make sure you are equipped with a phone and torches.

"We really want people to stay as safe as possible - thank you."

Fire crews earlier said they've been "inundated" with offers of support and warned people to stay safe as the light faded.

Officers and other emergency services - including the coastguard and firefighters - were trying to find the boy.

A helicopter was also scrambled to the area, along with three fire engines.

Firefighters said swift water rescue equipment including special and support vehicles, a water safety unit, and an inshore boat were all being used in the search.

Paramedics, a Hazardous Area Response Team, and the coastguard were also at the scene.

The search for the missing boy

In addition, drones were being used and members of the public made their way to the scene to help.

A briefing for local people helping in the search was held at Sandwich Fire Station at 7pm.

But as light faded, a police officer at the scene said: "At the moment we're hoping that he has been able to grab hold of something and pull himself out."

The coastguard helicopter has been supporting efforts to find the boy.

"Those who are helping are advised to attend to understand how they can assist in the search in a safe way, without placing themselves at risk, especially as the light begins to fade."

In a briefing at 7.40pm, the spokesman added: "We've been inundated with offers of support - thank you.

"However, the emergency services want to advise that as light fades, we need people to consider their safety and the risks associated with water.

"Unless you attended the briefing at Sandwich Fire Station and are aware of how you can help at this time, we would really encourage you to remain safe in your homes.

"We have a lot of help - thank you."

The fire service has also issued advice for those in the search for the six-year-old:

• Stay a safe distance from the water edge on the banks, do not enter the water
• Remain in contact with others and have a phone with you
• As light fades make sure you have a torch and you are sticking to the main tracks

There are two zones local people are helping with:

• Zone 1 - From Castle Cottages heading upstream

• Zone 2 - From the Toll Bridge towards the coast

Police superintendent Amanda Tillotson said: "Whilst we appreciate the support we have received from members of the public who wish to help in the search, we would strongly advise people to stay away from the water.

"This is for their own safety and to ensure those working within the emergency services can focus solely on locating the missing boy."

Anyone who wishes to report any details regarding the incident should call oolice on 101 or 999 in an emergency.

Read more: All the latest news from Sandwich