Fiji's National Federation Party says it does not pay anyone to make comments on social media platforms except on official NFP sites.
Party leader Biman Prasad said he's concerned at a police raid of the NFP headquarters this week in search of documents.
The interim opposition leader has dismissed claims by police the party had paid a volunteer during the 2018 election campaign to make anti-government posts on social media.
"[The] claim after a year and a half that the party paid him to post social media stuff is not only ridiculous but a complete lie," he said.
Mr Prasad said he does not know what crime the party's suspected of.