Almost 70 fires are burning across Queensland, with police and emergency responders warning that some fires involve “purposeful and malicious” behaviour.

Around 400 people are in emergency evacuation centres near the beach suburb of Peregian as fires still rage and more than 1000 firefighters and 250 firetrucks have been deployed across the state.

Queensland’s police commissioner Katarina Carroll said on Tuesday that a taskforce had been established to investigate the fires.

“There are many, many charges that have already been laid in relation to this,” she said.

“Some of the behaviour has been unfortunately reckless and other behaviour has been purposeful. Some of the fires have involved children playing and obviously the consequences are dire as a result of that and, as I said, some of them have been purposeful and malicious.”

Carroll said the task force would stay in place until she is satisfied that all the fires have been dealt with.

“The consequences of some of these fires are dire,” she said. “People can die. Buildings and residences are being destroyed and obviously some of them can carry life imprisonment offences if it is found to be purposeful and people do die as a result.”

Queensland Police said in a statement to Pedestrian.TV that detectives were already investigating the cause of one fire which started in bushland off Koel Circuit in Peregian Springs on Monday afternoon.

“Detectives are speaking with a number of teenagers in relation to the matter,” said the statement.

On Saturday, Queensland Police arrested three boys aged nine, 10, and 11, alleging the trio had lit a fire on the Gold Coast which did not spread to bushland.

On Monday the heritage-listed Binna Burra Lodge was “fully destroyed” by one of the fires. More than 20 homes have been lost since Friday.

Elsewhere, on the NSW north coast, planes are being used to drop fire retardant near properties that could be at risk when fires spread.