Multiple people have been reported injured after an explosion in a historic district of Istanbul popular with tourists, Turkish media reported Tuesday. Private NTV television said the explosion in the Sultanahmet neighborhood was close to a park that is home to a landmark obelisk. The state-run Anadolu Agency says several police and medics were sent to the area. Police sealed the area, barring people from approaching in case of a second explosion. Sultanahmet is Istanbul's main sight-seeing area and includes the Topkapi Palace and Blue Mosque.