Frankfurt Airport trains return to normal after fire

Trains between Frankfurt Airport and Cologne returned to normal on Wednesday morning after the service experienced massive delays due to a devastating fire in the German town of Siegburg.

The fire, which broke out on a grassy area near a key railway route, left at least 32 people injured and destroyed nine nearby houses.

The blaze forced high speed trains travelling between Germany's busiest airport at Frankfurt and North-Rhine Westphalia (NRW), the country's most populous state, to divert onto regional tracks going along the Rhine River. Passengers faced up delays of up to 90 minutes.

Meanwhile, regional trains within NRW continued to experience a limited service on Wednesday, as the route between Siegburg and the town of Troisdorf remained closed.

A spokeswoman for Deutsche Bahn told DW that the company's focus was on repairing the damage caused by the fire to the train and rails,  while also resuming normal service on all train lines. Only then could the rail operator formally assess the financial costs of the fire.

Deutsche Bahn also announced that it will contribute half a million euros to an aid fund for those affected by the fire. "Those who have seen the pictures will immediately see that fast assistance is needed," the spokeswoman said. "Since locals know best where support is most urgently needed, we are heeding the call for donations from our neighbors."

Read more: Can Germany's supposedly crumbling infrastructure hold up against extreme heat?

Cause of Siegburg fire still unknown

Visiting the scene of the blaze on Wednesday, North Rhine-Westphalia's Interior Minister Herbert Reul said that investigators were still probing what caused the fire.

Reul described the atmosphere as "very depressing," adding that he had never seen an entire street effectively be "burned away." However, at the same time he praised emergency services for successfully limiting "this insane fire."

A spokesperson for the Siegburg municipality had initially stated that the fire was likely caused by sparks from the tracks, which erupted into a blaze due to the ongoing heatwave and drought currently affecting Germany. However, they were forced to backtrack later, saying other causes shouldn't be ruled out. Investigators have even said they are looking into the possibility of an arson attack.

Christian Schindler, chair of the Institute of Rail Vehicles and Transport Systems at Aachen University, told the dpa news agency that he had never seen sparks from a train cause such a large fire. Further, sparks are usually only caused when a train conductor is forced to hit the emergency brakes or when the train goes into a sharp curve. 

Read more: Germany's autobahns crumble in early summer heat

Angela Merkel sends her well wishes

A spokesperson for Angela Merkel said the German chancellor gave her thanks to the 550 firefighters who battled the blaze late into the night.

The firefighters had "prevented worse things from happening and at the same time did extremely hard work," Merkel's deputy spokesperson Ulrike Demmer told journalists in Berlin. "The chancellor wishes all those wounded a speedy recovery."