Japan will do its utmost to free two of its countrymen believed to be held captive by the Islamic State militant group, Prime Minister Shinzo Abe said on Wednesday, Jan 21, adding that Tokyo would never give in to terrorism, Reuters reported.

"I have instructed (the government) that we will exhaust all possible measures to have the two freed, using all diplomatic channels, all diplomatic routes we have built so far," Abe said. "Our country will never give in to terrorism."

Islamic State released an online video on Tuesday purporting to show two Japanese captives and threatening to kill them unless it received $200 million in ransom.