French foreign ministry said on Thursday media reports on the release of seven French nationals seized in northern Cameroon could not be confirmed.

The French captives were found unharmed and abandoned in a house in the town of Dikwa in northern Nigeria and were with Nigerian authorities, French television BFMTV cited military sources as saying.

But in a statement posted on its website, the ministry noted that the reports on hostages' release "could not be confirmed," warning against the "spread of premature information."

Didier Le Bret, a director of crisis cell at the foreign ministry, said the reports were "unfounded."

"After verification with our embassies, this information appears unfounded. Concerned governments of Nigeria and Cameroon have also denied (the information)," said Le Bret.

"Immediately after the circulation of the rumor, the Quai d'Orsay (foreign ministry) via the crisis cell has first informed the families that this information ... should be taken with utmost caution," he added.

France's minister for veterans' affairs Kader Arif also told parliament earlier Thursday that there was no official confirmation at this stage, although he had interrupted a session minutes earlier to announce the release of the hostages, according to media reports.

Speaking to the local broadcaster Europe 1, a diplomatic source said there would not be an official confirmation until "hostages would be in hands of French diplomats, which is not the case now."

Cameroon's Communication Minister Issa Tchiroma Bakary on Thursday told Xinhua that the government is awaiting more details before confirming the information that French hostages were found in neighboring Nigeria.

Early in the morning, while meeting with journalists of the French media based in Cameroon, the minister denied the information on the release of the French hostages and termed the information as "rumor."

A Nigerian military spokesman also said the reports on French hostage release were "not true."

So far, no group has claimed responsibility for the kidnapping. French authorities said the Islamist Boko Haram cell was likely to be behind the incident.

The hostages, including four children, were captured on Tuesday by a group of armed men on motorbikes near the Waza national park and Lake Chad where Westerners often visit during holidays.

French foreign ministry on Wednesday urged French nationals to leave northern Cameroonian area "as soon as possible."

French Defense Minister Jean-Yves Le Drian on Wednesday said the abduction was not linked to the country's ongoing military operation in Mali.

However, following its military commitment in Afghanistan and Mali, France has become a top target of Islamist extremists who warned French safety was at risk "wherever they find themselves in the Muslim world."

Seven other French expatriates were still in the hands of al-Qaida-linked groups in the Sahel region.