A 37-year-old man has been arrested for allegedly sexually assaulting a female under 16 years of age, who was not known to him, NT Police said.

The incident occurred in the Palmerston CBD late on Wednesday afternoon, police said, but offered no further details.

“Detectives from the Child Abuse Taskforce identified and arrested the alleged offender earlier today,” police media director Mark Wilton said in a statement.

“The offender was not known to the victim.

“He remains in police custody, with charges expected to be laid later this evening.”

Police did not say where the suspect was arrested.

No description of the man was provided or the exact location of the assault, however police are asking anyone who has information to contact them on 131 444 or anonymously through Crime Stoppers on 1800 333 000.