Papua New Guinea football coach Flemming Serritslev says police had to be called after people connected with the rebel Football Federation PNG interrupted a training session for the national team.
The Kapuls are in camp preparing for next month's home and away FIFA World Cup qualifying matches against Solomon Islands.
Flemming Serritslev has only selected players for international duty who are competing in the National Soccer League, which is recognised by the PNG Football Association, Oceania Football and FIFA.
"Some hooligans and officials from "Fake Football Federation" entered our pitch, entered out training, interrupted our training and we had to stop the training 45 minutes before schedule," he told EMTV.
"Had to call the police to take care that everything went on in a good way - it's unbelievable what is going on in this country when it's about the national team.
"Unfortunately, I have to say, there are a few people who does everything they can to destroy the work of the national team."
The Kapuls were named team of the year at the PNG Sports Awards in Port Moresby on the weekend, following their runners-up finish at the 2016 OFC Nations Cup.
Flemming Serritslev said the award served as as a big motivation for the team for the upcoming matches against Solomon Islands.
Football Federation PNG was launched by former PNGFA Vice President John Kapi Natto earlier this year, after the Hekari United owner was suspended by the PNGFA for making derogatory comments.
The breakaway National Premier League has 12 clubs compared to six in the NSL but their players are not eligible to be picked for the national team.