POLICE in Germany have stormed a second apartment in the city of Chemnitz in the hunt for a bogus Syrian refugee after discovering a kilo of explosives in his home on Saturday.

The same explosive was the substance used in the terrorist attack in Brussels in March this year by suicide bombers who killed more than 30 people.

17 Suspect Jaber Albakr is still on the run with police warning residents to stay inside and be careful

17 Special police forces use ladders as they make their way into an apartment in Chemnitz, on Sunday Credit: AP

17 It was the second apartment raided in the city in connection with a suspected terrorism threat Credit: EPA

17 Police arrested a man they say was the accomplice of Jaber Albakr who is on the run Credit: EPA

On Sunday, as the hunt for Jaber Albakr, 22, was stepped up, another apartment in the eastern city was raided by heavily armed officers of the specialist SEK unit.

A stun grenade was hurled into the apartment on Sunday before cops stormed it and one man was arrested.

A woman and a child were also in the apartment and they had to be treated for shock.

It is understood the arrested man is an accomplice of Albakr, who came to Germany in February last year on a Syrian passport via Austria.

On Saturday three other men suspected of helping him in a plot to bomb a regional airport were also seized in Chemnitz.

Albakr, slipped through the fingers of security services, despite having been under surveillance, prompting cops to warn residents to stay off the streets.

17 Three people have provisionally arrested as armed police hunt a suspect connected with a planned bomb attack Credit: EPA

17 Residents were yesterday told to stay inside while cops hunt suspects Credit: DPA

17 A remote controlled robot examines the luggage of two people arrested at the city's train station Credit: DPA

In a tweet on Saturday afternoon Saxony Police said: "The search for the suspects running. Currently, however, we do not know where he is or what he carries with him. Be careful."

Earlier today scores of armed officers blew the door off a flat in and discovered "highly sensitive explosives" but not "a person of interest".

Tom Bernhardt, spokesman for the state criminal police in Saxony said officers acted on intelligence received on Friday night and that their actions have foiled a "serious threat".

He added: "We must assume that the person is dangerous."

Mr Bernhardt said it was unclear if one or several suspects were involved.

Intelligence agencies say Albakr learned his bombmaking skills from ISIS in his homeland. While the ingredients for the explosives found are easy to come by, the assembly of a DIY bomb from them is extremely technical.

17 Police made another arrest following a raid on a second apartment on Sunday Credit: EPA

17 A police officer in protective clothing watches on as a remotely controlled bomb disposal robot lifts a suitcase on a platform Chemnitz Central Station Credit: EPA

17 Armed police raided an apartment this morning and found highly sensitive explosives Credit: AP:Associated Press

Yesterday it was revealed that Albakr had been on the radar of the internal intelligence service, the Office for the Protection of the Constitution, for months.

On Friday the Cologne-based agency contacted law enforcement personnel in Chemnitz to say that his plan was about to be put into force. An entire area of the city around the Usti nad Labem street in an area called the Fritz-Heckert settlement was cordoned off.

Police took to social media and used loudhailers to tell residents to stay indoors and away from windows. "It is about the suspicion of preparing a bomb attack," said local police.

Although no-one was found at the apartment two men were later arrested at Chemnitz main railway station, one near to the apartment building where the apartment was searched. At the railway station a robot was deployed to remove a suspect suitcase authorities feared might contain another bomb.

17 On Sunday the manhunt escalated as cops detained a man said to be linked to Syrian migrant suspect Albakr Credit: EPA

17 They raided a second apartment in the eastern city of Chemnitz Credit: EPA

17 A broken window can be seen at an apartment in the Yorckgebiet district of Chemnitz Credit: DPA

17 Jaber Albakr however still has yet to be tracked down by police in Germany Credit: AP

The Bild newspaper, Germany's largest selling daily, reported that the trio had travelled from Leipzig to meet with Albakr. He had fled before the police arrived.

"He is a dangerous person and should not be approached," added Bernhardt.

Albakr, who was born in Damascus, came to Europe from the Syrian town of Saasaa. His target in Germany was reported to be a regional airport, possibly Dresden or Leipzig.

Police have appealed for information on his whereabouts. The foiling of the plot came weeks after German intelligence officials said there were at least 520 suspected ISIS terrorists among the waves of refugees waiting to strike for the death cult.

Families living in the block of flats told MDR Sachsen they were woken by police with machine guns telling them to leave the building and were removed from the area by bus.

17 The city's train station was temporarily closed as police hunt for a suspect after foiling a bomb plot Credit: DPA

17 A special unit police unit in the east German city of Chemnitz Credit: DPA

17 There is a huge police presence in Chemnitz as police hunt a suspect believed to have been planning a bomb attack Credit: Ruptly

On Saturday evening cops removed the outer cordon, allowing some residents back into their homes.

A spokesperson for Saxony Police said: "We are carrying out a large operation in Chemnitz following suspicion of preparations for a bomb attack.

"Major road closers and evacuations are necessary.

"Please stay within the cordoned-off areas in your homes and follow the instructions of police."

Germany had until the summer been spared the kind of militant attacks suffered by neighbouring France and Belgium.

But in late July, Islamic State claimed two attacks - on a train near Wuerzburg and at a music festival in Ansbach - in which asylum-seekers wounded 20 people in total.

German Chancellor Angela Merkel's open immigration police has come under fire following the attacks.

German police said previously they had identified 523 people who posed a security threat to the country, around half of whom were known to be currently in Germany.

Fear of terrorists hiding out among the migrants caused Merkel's approval ratings to plummet last month and she has lost heavily in regional elections to the anti-immigrant Alternative for Germany (AfgD) party in recent months.

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