Haruna Yukawa, a Japanese private mercenary poses in Aleppo. The Japanese national has now been captured by the ISIS militants.
Haruna Yukawa, a Japanese private mercenary, poses in Aleppo in May. ISIS claimed on Saturday that he has been beheaded.Facebook/Haruna Yukawa

While Tokyo is still to confirm the identity of its citizen, who is being held by the Islamic State in Syria, reports indicate that the captured Japanese man is a private mercenary, who may have fought along with the Free Syria Army.

The Foreign Ministry in Tokyo confirmed on Sunday that it has received information that a Japanese national has been captured by the Islamic State militants in Aleppo, northern Syria.

The government, however, is yet to verify the information, including the man's identity and the authenticity of the two video clips that show the Japanese national in captivity, Japan Times reported.

In one of the videos released by ISIS, a man wearing a black Tee can be seen lying on the ground while being questioned by unidentified persons.

He tells them he is a Japanese national and that his name is Haruna Yukawa. The abducted national also claimed that he was part journalist, part doctor.

A Reuters report stated that the captured man could be the head of a Japanese security firm, PMC (Private Military Company) Co Ltd.

Haruna Yukawa, on his Facebook account, has put up several pictures that confirm his presence in Syria.

A video posted on 11 July show him test firing an assault fire in Aleppo. While there are dozens of pictures that show him posing in an armoured vehicle.

An adviser to the firm, Nobuo Kimoto, told Reuters that Yukawa had travelled to Syria earlier this year "because he thought it would be useful for his work".

Regional representative of nationalist group "Gambare Nippon" (Stand Firm, Japan), Kimoto, also said Yukawa was active in the group.

The government-affiliated news website Syria Now in its report noted that the Islamic State captured a terrorist mercenary from Japan, who was fighting along with the Free Syrian Army.

It is feared that the Japanese national may have accompanied the FSA in a battle and could have fallen into the hands of the brutal Islamic State.