Police and Search and Rescue teams with dog units are combing the forest and beach to try to find Alex and rescuers are asking the public to stay away while the dogs work to find tracks in the area.
A police spokeswoman confirmed "items thought to have belonged to the boy have been collected by police".
She said the police would continue the search into the night and a fresh set of searchers were brought in at 9pm to relieve the existing parties.
"They are getting in more people. They are increasing the amount of staff that will be searching," the spokeswoman said tonight.
"The person in charge will then make a decision a couple of hours later to see what they are going to do at that point.
"They do hold concerns for his safety and they are going to continue the search for as long as they can."
Land Sar staff get ready to comb Waitere Forest and beach as they search for missing 10-year-old Alexander Fisher who was last seen by his family on Monday evening.
A Waitarere resident, who asked not to be named, said the domain area where the boy was last seen was a busy hang-out for children and families during the day.
There weren't any camping facilities there, but there was a BBQ area.
"The domain is our main playground for our children. It's got a Scout hall, a field, tennis courts there, that sort of thing. It's a popular area."
Hydrabad Holiday Park and Waitarere Beach Motor Camp owner Deborah Nichol said police helicopters were at work and one had just landed across the road from the motor camp.
"The place is crawling with cops and LandSAR guys."
She said the southern block of the forest, where rescuers were, was about 15 square kilometres.
"It's not huge. Roughly we're looking at between 4 1/2 and 5km from the southern entrance to Hokio Beach and then it's about three or four kilometres wide."
Mrs Nichol found about the search mid-morning after campers were stopped by police in the domain, just behind the camp.
Police and land SAR teams search for missing 10-year-old Alexander Fisher at Waitarere Forest. He has been missing since Monday night.
Tony Strawbridge, who runs the Windy Waves Bed and Breakfast, said the temperature in the seaside town today was about 15 or 16C.
The southern block of forest, where the search was concentrated, was a fenced area with cycle tracks."It would be very hard to get lost in there," he said.
"As locals we've been asked just to keep out of the forest. They've got a helicopter I've seen going up and [the searchers] are using the local fire station as a base."
