German police arrest six men suspected of planning Berlin half-marathon attack

Main suspect reportedly had two sharpened knives to carry out stabbings

Suspects allegedly planned to carry out knife attack on spectators and runners at Berlin's half marathon (AFP/Getty)

Police in Germany have detained six men on suspicion they were planning to carry out an attack at Berlin’s half-marathon on Sunday.

“There were isolated indications that those arrested, aged between 18 and 21 years, were participating in the preparation of a crime in connection with this event,” prosecutors and police wrote in a joint statement.

Berlin police tweeted to say six people were detained in cooperation with the city prosecutor’s office.

The German daily newspaper Die Welt first reported on police foiling a plot to attack race spectators and participants with knives.

The newspaper said the main suspect was allegedly linked to Anis Amri, a failed Tunisian asylum seeker with Islamist ties who hijacked a truck and ploughed it into a crowded Christmas market in Berlin, killing 12 people and injuring dozens of others.

Police spokesman Thomas Neuendorf told local broadcaster RBB the evidence of a viable and imminent attack was not yet confirmed.

“They were very vague indications, but because of the high threat level we immediately started with our police searches and arrests,” Mr Neuendorf said.

“But at the moment there are no really concrete indications that an attack on the Berlin half-marathon was foreseen.”

One of the apartments Berlin police raided before the race started Sunday was also searched after the Christmas market attack, the report added.

It said special police forces detained four men in connection with the race plot – a different number from the six arrests the police reported.

Die Welt’s report said the main suspect, who was not identified, had prepared two knives which had been sharpened especially for use in the attack.

It also said that in one of the searched apartments, dogs trained to find explosives barked when they were taken into the basement.

Mobile phones and computers were among the confiscated evidence being examined, Mr Neuendorf said.

The police spokesman added there had been “no danger at any time for the runners, participants and staff” during the race, which organizers said attracted some 250,000 spectators.

Mr Neuendorf told German news agency DPA the investigations were centered on people "whom we regard are associated in the Islamist-terrorist area."

The main suspect had been under observation for two weeks around the clock, local daily Tagesspiegel reported.

After a foreign intelligence service tipped off German authorities that he was planning to attack the half-marathon, police raided apartments and two vehicles in the Charlottenburg and Neukölln districts of the city.

The half-marathon was being guarded by some 630 police officers, DPA reported.

Amri’s attack prompted German lawmakers to call for tougher security measures.

No major Islamist militant attack has been carried out in Germany since.

Earlier on Sunday, Germany’s interior minister, Horst Seehofer, said the government would do everything possible to protect citizens, but added: “We have again experienced that ... absolute security is unfortunately not possible.”

Mr Seehofer was speaking in Münster, where a man drove a van into a group of people sitting outside a restaurant on Saturday, killing two of them before shooting himself dead.

Authorities said the attacker was a 48-year-old German citizen with mental health problems and there was no indication of an Islamist militant connection.