German police were Thursday searching for a man after he fled a police check at a busy Berlin railway station and left behind a backpack containing explosives.

Officers approached the man in Berlin's Neukoelln station at around 3.30pm on Wednesday afternoon, police said in a post on X.

"The man fled and left behind a bag in which the police found explosives," they said. 

The bag was taken to a nearby park to be "detonated there in a controlled manner", they said, adding that the area had been cordoned off and there was no danger to residents.

The background to the incident was still unclear, police said Thursday.

According to the Bild daily, the backpack contained "a greyish substance, a plastic bottle wrapped with wires and a paper bag with more cables".

The substance was the highly explosive TATP, which has been used in several high-profile Islamist attacks, Bild said.

"If this explosive device had gone off in the vicinity of a group of people, it would have had dramatic consequences," Berlin's BZ newspaper quoted a police officer as saying.

Firefighters dug holes in the ground before the substance was detonated, according to Bild, which said the explosion could be heard several hundred metres away.

Dirk Wiese, an MP from Chancellor Olaf Scholz's SPD, said police "were obviously able to thwart an attack". 

"This clearly shows how high the terror threat is in our country," he told the Rheinische Post newspaper.