Police ordered the evacuation due to coolant leaking into the building. Germany has been experiencing unusually high temperatures.
Hamburg's central train station was completely evacuated and closed to the public on Friday. The measures were taken after a cooling agent reportedly began leaking from a pipe, prompting fears of an explosion.
"The coolant began leaking under pressure, and was dispersed inside the building," a spokesman for the northern German city's fire department told the daily tabloid Bild.
Local newspaper Hamburger Abendblatt reported that a large contingent from the police and fire department had locked down the area, and that train traffic in and out of Hamburg had come to a complete standstill.
While the trains inside the central station had been evacuated, the police ordered all other regional trains in the city to remain at their current stations and allow passengers to disembark, due to the relatively high temperature Germany is currently experiencing.
Photos of the Hamburg central station showed rows of police cars and fire trucks surrounding the building.