SIS and police have raided several Auckland properties in connection with an alleged plot to assassinate Fiji's leader Voreqe Bainimarama.

A former Fiji cabinet minister, Rajesh Singh, said the officials, armed with a search warrant, seized his daughter's laptop computer and his cell phone yesterday.

Several other Fiji nationals have told Fairfax they were also visited.

LAPTOP, CELLPHONE SEIZED: Former Fijian cabinet minister Rajesh Singh denies knowing anything about an alleged plot to assassinate Fiji's leader, Voreqe Bainimarama.

A spokesman for Prime Minister John Key refused any comment.

"This is an operational matter. We have no comment on security and intelligence matters."

Singh said the security officials told him that they had "credible evidence" that the assassination was planned in Auckland a fortnight ago during a visit by Fiji Army Colonel Tevita Uluilakeba Mara.

Colonel Mara, who is wanted on charges that he was plotting to overthrow Bainimarama, fled Fiji in May last year and has refuge with the Tongan royal family, to whom he is related, in Nuku'alofa.

Mara was in Auckland two weeks ago.

Singh said a woman who he named said she was from the SIS and that she had a warrant to search his place.

He asked for a copy of the warrant but was told it was classified and he could not have it.

She was accompanied by three plain clothed police.

They took away the computer and cell phone and gave him a blank receipt for it, which included the SIS's 0800 number.

"They said: 'We heard Mara came here' and I said: 'Yes, Mara comes here every time, we have been friends for 40 years'."

They told him they had "credible evidence" that Mara and another New Zealander were planning to assassinate Bainimarama and his attorney general Aiyaz Sayed Khaiyum.

"I said that was news to me... I said it never happened, we never talked about those things."

Singh and others visited were members of a small Auckland based group, Coalition for Democracy in Fiji which is called for the restoration of democracy.

Singh said they took his cellphone. He said he regularly texts Bainimarama who replies to him now and again.

They returned the computer and cellphone later in the day and thanked him for his cooperation.

"They said don't talk to the media, don't talk to anybody because the Fiji regime doesn't know anything," Singh said.

"I said if you think Mara is involved you should talk to him, not me."

Mara is in Tonga and could not be immediately contacted.

Bainimarama seized power in a military coup in 2006.

There has been one known attempt to kill him when his own soldiers mutinied in 2000. Eight soldiers died in the attack which saw Bainimarama run away for safety.

In 2007 a Fiji Indian of New Zealand citizenship, Ballu Khan, was arrested in a plot to kill Bainimarama.

Khan was severely beaten but managed to get out of Fiji and now is believed to live in Auckland.

Eight other people, including paramount chief Ratu Inoke Takiveikata and former Fiji spy service chief Metuisela Mua were convicted of the plot and jailed for life.