An 18-year-old who allegedly spat at, punched and kicked five police officers during an arrest at an Alice Springs bottle shop on Saturday has been charged, NT Police said, as the union representing police have called again for mandatory imprisonment for those found guilty of assaulting cops.

In the latest incident, police said the man was identified as having an outstanding warrant during a point of sale intervention at the unnamed Alice Springs liquor store where officers attempted to arrest the man.

But he resisted and allegedly punched one of the officers several times to the head, causing a mild concussion, while also attempting to bite police, a statement issued by police said.

Another officer reportedly attempted to assist the first officer when the teen allegedly spat at and attempted to bite the second officer.

Police said another three off-duty officers became involved while the man continued to resist, allegedly kicking and spitting at the group of police.

“He was eventually controlled and conveyed to the Alice Springs Watch House, where he remained uncooperative and allegedly again spat directly into the faces of attending officers,” said Acting Superintendent Michael Milde.

Supt Milde said the officers all attended Alice Springs Hospital for disease testing and one officer was treated for a mild concussion and other minor injuries. Police said all returned to duty to complete their shifts.

The latest incident comes amid a crime crackdown in Alice Springs announced by police last week to deal with increased incidents of random assaults and property crime in the troubled town.

“The offender’s behaviour is disgusting and the fact that our officers returned to duty following this incident is testament to the dedication of our members,” Supt Milde said.

NT Police Association president Paul McCue said the 18-year-old who allegedly assaulted the officers was on a suspended sentence for two previous assaults on police and called for mandatory imprisonment terms for anyone convicted of assaulting NT police officers.

“What is it going to take for the government to listen to our concerns?” Mr McCue said in a statement. “How many times do our officers need to go home injured before reform actually occurs?

“The NTPA has waited for months for an update from the Gunner Government’s working group on assaults on workers. We are still waiting for that update.

“These members now face an anxious wait for test results to see if they have contracted a communicable disease.”

St John Ambulance staff were also spat on during an isolated incident on Friday in Darwin’s northern suburb of Karama.

Police said the Alice Springs 18-year-old was charged with five counts of assaulting police, three counts of resisting police and two counts of breaching bail. He was to appear before Alice Springs Local Court on Monday.