The armed man in question appears to be a robber armed with a handgun, AFP reports.
Police special forces are at the site, the French Lexpress reports, adding that law enforcement has cordoned off the area near the place where the hostages are held.
The incident is believed to be taking place in the Asieland travel agency on Boulevard Massena, in the city’s 13th Arrondissement.
On its official Twitter account, police have called on people to bypass the area. Reuters is reporting that the travel agency has been held up in the past and is particularly popular with Asian customers who deal in cash transactions. Paris police have tweeted that six people have been evacuated from the office. The gunman remains inside, however.