Two Marlborough men have been arrested in connection with the brutal deaths of 23 seals near Ohau Point, north of Kaikoura, in November.

The men, aged 35 and 19, have been charged with aggravated cruelty to animals, and possession of an offensive weapon, and are to appear in Blenheim District Court on Monday.

Police would not say where in Marlborough the men were from.

The fur seals were beaten to death in what was described by the Conservation Department (DOC) as a "callous and cowardly" attack, which shocked locals and tourists visiting the site.

Some were just a few days old. The dead seals also included 13 females and two bulls. Other live seals had injuries that suggested they were also struck.

At the time, DOC said it believed the attacks had been carried out over days. When they were found in the first week of December, some of the seals had injuries that could have been a week old. DOC south Marlborough area manager Dave Hayes said his office received a tip-off and the department was pleased with the news of the arrests.

"This was always going to be a case which relied on information coming in from the public, and we're pleased the public has continued to be incensed enough to pass on the information."

Mr Hayes said information had been coming in "dribs and drabs", and while the investigation had seemed to slow down over the past few months, collaboration between the police and DOC had worked well.

The department would probably also lay charges, Mr Hayes said.

"We would lay charges under the Marine Mammal Protection Act, so we are just considering our options now."

When told of yesterday's arrests, Seal Swim Kaikoura co-owner Matt Chambers said he was "over the moon".

"I'm stoked. My hope is that now some kind of example is made so a strong message is sent out that it's not OK to go around bashing defenceless animals," he said. "We will be very happy to see some decent punishment, which is worthy of the crime."

Fur seals are protected and it is an offence to kill or harm them.

The penalties include a fine of up to $250,000 or imprisonment of up to six months, plus fines for each animal killed.

OTHER SEAL ATTACKS

Earlier this week, two men accused of bashing a fur seal that later died denied charges against them in Waitakare District Court. Tomoare Angoika and Matthew Botica said they were simply trying to release it from their net. The female seal pup was found injured in Henderson Creek in January.

Last November, a 20-year-old Southland man was jailed for four months for his role in an attack on a leopard seal in October last year. Fist-sized stones were thrown at the seal and it was dragged around a beach by its tail. Two other men were fined, $5000 and $7000 respectively, for their parts in the attack.

In July, Hayden John Ingram was sentenced to community work and fines after he ran over a seal pup at the Point Keen colony and beat an adult with a steel pole, killing both animals, in June. A youth has also been charged with cruelty and will be dealt with by the Youth Court.

In 2005, three men, including All Black Andrew Hore, were each fined $2500 in relation to shooting at seals, killing one, on the Otago coast.