There have been disruptions to Anzac services in New Zealand, Australia and the United Kingdom.
In Waiouru, a motorcycle gang has been accused of disrupting a dawn service by firing up a bike during the Last Post.
An Auckland woman, Andi Brotherston, who was at the service, took a video of the Rebels gang starting their bikes and driving away.
In the video, the sound is much louder than the bugle of the Last Post.
Ms Brotherston said it was very disrespectful and people at the service were very angry.
A spokesperson for the National Army Museum said motorcycle gang members who revved their engines during the dawn service in Waiouru didn't succeed in destroying the atmosphere.
Nicola Bennett said about 1,000 people attended the ceremony.
She said it was not clear whether the bikers were trying to be intentionally disruptive.
She said many of those who attended the dawn service in Waiouru had travelled from other parts of the country to be at the army's "spiritual home".
Other activities at the museum today included parades, historical talks and the opening of its new Gallipoli exhibition.
Vandals target Australian war cemetry in England
The main Australian war cemetery in the UK has been targeted by vandals who sawed through a flagpole and spray-painted a memorial on the eve of Anzac Day.
The attack took place at St Mary's churchyard in Harefield in Middlesex, outside London.
More than 100 Anzacs and one Australian nurse, treated at the nearby Harefield Hospital during WWI, are buried on the site.
The Commonwealth War Graves Commission (CWGC), which looks after the graveyard, said today's Anzac Day service would still go ahead, after repairs had taken place.
"Disgusting, absolutely disgusting, for what these lads gave up for us - to be treated like that is just shocking," the commission's Barry Rushton said.
The graves at Harefield have a unique scroll design which was chosen by Anzac patients brought to Harefield - then known as Australian Auxiliary Hospital No. 1 - for treatment from Europe and the Middle East.
Earlier this year the CWGC restored the graves of the Australian servicemen buried at Harefield.
"Ahead of the ceremony, we will either make a clean cut through the pole and have it erected at a lower height, or we will support the pole with brackets," a CWGC spokesman said.
"It will be safe and usable for the ceremony.
"The vandalism is very upsetting for the Commission after all the work that has taken place over the last three months."
Harefield's annual Anzac Day service, which features local school children laying flowers on every grave, started in 1921.
A new visitor information panel featuring smartphone technology revealing the personal stories of some of those buried on the site was also targeted by the vandals.
The CWGC said it was not yet known if the panel unveiling will go ahead.
A man who burned an Australian flag in front of Brisbane's Shrine of Remembrance has been banned from attending any Anzac Day services and ordered to leave Brisbane.
Peter Di Iorio, 66, was charged with public nuisance and remanded in custody overnight after the incident, which was filmed by news crews in Brisbane's CBD on Friday afternoon.
Police prosecutor Senior Sergeant Mark Gorton did not oppose Di Iorio's bail on the condition that Di Iorio be banned from attending all Anzac Day services.
"That way he can't go out and make a spectacle of himself," Senior Sergeant Gorton said.
Magistrate Linda Bradford-Morgan granted the condition, ordering police escort Di Iorio back to his car in Brisbane's CBD.
She ordered him to immediately leave Brisbane and return to his home in Palm Beach on the Gold Coast once he had found his vehicle.
Di Iorio is due to appear again in the Brisbane Magistrates Court on May 27.