Attention was focused on trying to save Kenji Goto, a 47-year-old journalist who was shown in the video.
Down the road, a police poster on a tree reads “Terrorism has no religion”.
Abe said the government would spare no effort to secure the release of the remaining captive.
“We will never give up. We will bring them home,” said Deputy Foreign Minister Yasuhide Nakayama.
The agency found that since location of the IP address was “masked”, it was difficult to decipher.
The posting which appeared Friday shows a clock counting down to zero.
Their capture by the Islamic State group has created a sudden crisis for Japanese PM Shinzo Abe.
Obama said that the US military leadership in Iraq and Syria is stopping the Islamic State’s advance.
The teenager had gone missing in Turkey near the Syrian border.
NIA sources familiar with the case said they had not yet arrived at any conclusions about Tanki’s whereabouts or status.
The militants transported them from Tal Afar, where they were being held for the past five months.
Officials said the tip-off came directly from a US intelligence agency, which had been monitoring his movements ever since he left the US.
Islamic State is fighting both the Syrian army and rival insurgents along the edges of the territory it controls.
Attempts to secure passages to IS-controlled territories by flying to Saudi Arabia and Jordon are also made.
In the video, Coulibaly pledges allegiance to the Islamic State group.
Best of Express