An alleged rural bank robbery saw two would-be crooks walk away with four $5 notes and others "likely" covered in pink ink which exploded from three dye detonators.

Key points: Two alleged thieves who broke into the Katherine branch of the Bendigo Bank were last spotted fleeing towards Ryan Park

Two alleged thieves who broke into the Katherine branch of the Bendigo Bank were last spotted fleeing towards Ryan Park The pair are believed to have detonated two dye packs hidden between $50 notes

The pair are believed to have detonated two dye packs hidden between $50 notes NT Police have called on the public to pass on information if they spot people or bank notes stained by pink ink

Northern Territory Police say the thieves robbed the Katherine branch of the Bendigo Bank in the early hours of Saturday morning.

Police say the men forced their way into the closed bank after smashing the glass front door at about 3:45am.

NT Police put out a statement on the incident calling for information to help identify the intruders who "stole a number of items including three security dye packs which were hidden between $50 notes and appeared to be bundles of money".

"Four $5 notes were also stolen," police said in the statement.

Superintendent Daniel Shean branded the attack as "opportunistic", as opposed to a planned robbery, and said a forensic team was now working to gather evidence.

"The CCTV has been viewed in relation to trying to track movements prior to and after the incident," he said.

"It's probable that's there's going to be some forensic evidence at the scene that will also assist us in the investigation … we'd be looking at DNA and fingerprints."

NT Police are on the hunt for two alleged robbers they believe could be covered in pink ink. ( Supplied: NT Police )

Alleged robbers likely detonated dye packs

Police said the alleged offenders would likely have "unwittingly detonated" the hidden dye packs, "which release a fine pink powder that stains upon contact".

"The staining will have the appearance of pink ink and is extremely difficult to remove from skin and clothing," the statement said.

"The men, and the stolen money notes, are likely to have significant visible staining."

The two men had their faces and heads concealed during the alleged robbery, and were wearing dark clothing.

"As soon as they make attempts to separate the notes, the dye does explode over the person that is handling that cash," Superintendent Shean said.

Police say alleged thieves would be 'frustrated'

Superintendent Shean said the alleged robbers would have been "very frustrated" with their minimal haul.

"It is a lot of effort they've gone to for not much gain," he said.

"Ultimately at the end of the day, the cash amount they've gotten away with was very, very minimal, and the fact that they're going to be sustaining a pink dye on them … they'd be very frustrated in their efforts."

After the incident, police said the pair fled in the direction of Katherine's central Ryan Park.

"Anyone with information, or persons who may have witnessed this incident, are urged to notify police on 131 444," police said.

Last December, a Bendigo Bank branch in rural Victoria was subjected to extensive damage after thieves used an excavator to break through the front wall to steal cash.