"Citizens of Japan may be among the hostages taken in Bangladesh. We are checking information," Suga said at an emergency press conference in Tokyo.
On Friday, Daesh terrorist group outlawed in Russia reportedly claimed responsibility for hostage taking inside the cafe located in Dhaka's diplomatic quarter, which also reportedly left up to 40 people injured and two police officers dead.
Earlier, Italian Foreign Minister Paolo Gentiloni expressed his worry about the country's citizens involved in the hostage-taking incident.
"I follow the situation in #Dhaka moment by moment. In fear of Italians involved," Gentiloni posted to Twitter.
According to media reports, an operation to free the hostages is expected to begin in the next few hours.