But property crimes, including house break-ins and motor vehicle theft, plummeted due to community lockdowns, NT police say.

Domestic violence-related assaults surged 27 per cent and alcohol-related assault increased by 31 per cent in the 12 months from April 1, 2020.

Sexual assaults climbed by five per cent and non-alcohol-related assault was up 20 per cent compared to the same period a year earlier.

"Domestic violence is a shocking thing and it is a crime and we know how it affects children that are raised in those households," Commander Matt Hollamby told reporters on Friday.

"We're hopeful that current figures are a product of the pandemic and what we do as a police force and what our partners do to prevent domestic violence will see these figures dramatically reduce."

There were 5162 domestic violence-related assaults in the NT between April 1, 2020, and March 31 this year, up 1094 incidents compared to the 12 months prior.

Alcohol-related assaults climbed from 3239 to 4249 and non-alcohol-related assaults increased from 6760 to 8130 incidents.

"Most of it occurred during the pandemic period when people were at home, there was more money, including JobKeeper and JobSeeker," Mr Hollamby said.

"If you assault a family member we will go out of our way to prosecute you."

House and commercial property break-ins and motor vehicle thefts plummeted during the same 12 month period, falling 26, 28 and 29 per cent respectively.

"It accounts for the COVID period, including the lockdowns," commander Hollamby said.

"In Darwin, the total number of property offences is down by 22 per cent, which is the lowest 12 month period recorded in the last 20 years."

Mr Hollamby said there was a link between property crime and domestic violence.

"We find all our high-end recidivist youth offenders were exposed to domestic violence from a very early age and that's a really sad fact," he said.

Australian Associated Press