ACT Policing and the ACT Fire and Rescue attended six grass fires in Curtin and Weston.

About 1am on Wednesday crews attended two small grass fires on Curtin Oval and at 5.50am there were four grass fires on the Tuggeranong Parkway and Cotter Road in Weston.

ACT Emergency Services commissioner Georgeina Whelan said it was "extremely disappointing" fires had been deliberately lit when the ACT faced a severe fire danger.

"Given the catastrophic events that are occurring all across our country at the moment, the conditions we are facing which are already high risk as it stands, to think that a number of people would deliberately light fires in our community and put hundreds of thousands of lives at risk is something of concern for us," she said.

There was a total fire ban imposed on the ACT on Wednesday with a fire danger rating of very high.

Criminal investigations acting superintendent Matthew Reynolds said lighting a fire was a serious threat.

"Anyone who lights a fire is potentially putting people's lives at risk," said Mr Reynolds.

"Those who do the wrong thing can face penalties of up to $32,000 in fines or if someone dies as a result of a deliberately lit fire they could face serious criminal charges.

"ACT Policing officers are well aware of today's total fire ban and are mindful of this as they patrol the ACT."

Police were also investigating a suspicious house fire in Gilmore on Wednesday after fire and rescue attended the blaze at around 11pm on Tuesday night.

There was also a suspicious fire in Banks in the early hours of Tuesday.

ACT Police said they received two reports of fireworks being set off on New Year's Eve.

Police have asked people to come forward who may have seen anything suspicious in Curtin or Weston or have information about the fires including CCTV footage or dash cam footage.