Police arrested two men who they believe are connected to the two terroist attacks that were carried out by a native born Danish citizern who has links to gangs and spent time in jail for assault.

Danish media has identified the attacker as Omar Abdel Hamid El-Hussein, a 22 year old living in Copenhagen. He was released from prison two weeks ago after serving less than a year of a two year sentence for aggravated assault.

The Local (Denmark):

Two men have been charged with aiding the suspected gunman in the twin attacks in Denmark at the weekend, police confirmed on Monday.
 
A lawyer for one of the men had said earlier they were charged with helping the attacker get rid of his weapon and giving him somewhere to hide.
 
Police confirmed they had been charged with aiding and abetting the gunman but did not confirm the specific allegations.
 
The two suspects, who appeared in court on Monday following their arrest on Sunday, cannot be named for legal reasons.
 
Police had earlier announced the arrest of two men "suspected of aiding and abetting the perpetrator" of the deadly shootings at the Krudttønden cultural centre and the synagogue in Krystalgade.
 
Both suspects are from an immigrant background, tabloid Ekstra Bladet reported.
 
The gunman himself, who was killed in a pre-dawn shootout with police on Sunday, has been identified in the media as Omar El-Hussein, a 22-year-old with a history of violent crime.
 
Ekstra Bladet said he had been released from prison two weeks ago after serving a term for aggravated assault -- raising fears he may have become radicalised behind bars.

CNN is reportng that the suspect was "well known" to police:

While police haven't formally released the name of the gunman, they said he is a 22-year-old man born in Denmark.

Authorities said he was "well-known by the police for several criminal incidents," including weapons violations and violence. Police also said he was "known in connection to gangs."

Carsten Ellegaard Christensen, a national security reporter at the Danish newspaper Jyllands-Posten, provided additional clues, citing sources with detailed knowledge of the investigation.

Christensen was told the dead gunman was Danish-Arab, living in Copenhagen, and was on the radar of authorities for gang activity, not for suspected Islamist extremism. As far as police know, he had not traveled to Syria or Iraq.

The gunman was recently in jail after being convicted of stabbing another young man with a knife several times on board a commuter train, Christensen said. The man survived.

How did the gunmen get so close to the synagogue with the heavy police presence? He acted like a drunk:

The 22-year-old attacker responsible for the Copenhagen shootings over the weekend was able to fool policemen on Krystalgade near the synagogue by pretending to be drunk, reports Politiken.

Omar Abdel Hamid El-Hussein stumbled and weaved towards the synagogue, enabling him to get close to Dan Uzan, the man standing guard at the synagogue, and two policemen. He then pulled out his gun, killing Uzan and wounding the two officers.

Identity revealed
Police on Sunday were able to finally identify El-Hussein late on Sunday afternoon, despite shooting and killing him in the early hours.

It has been confirmed that El-Hussein was a former student of adult learning school at VUC in Hvidovre.

Peter Zinkernagel, the rector of the school, told DR that El-Hussein was a “very talented and gifted student who did well professionally”.

Talented, gifted...and a thug.

You don't have to go to prison to be radcialized. There's enough jihadist crap on the web that those most susceptible to becoming extremists have no trouble finding encouragement for their beliefs.

Did the three men meet at a mosque? How did they find each other? Chat room? It seems unlikely that they all just bumped into each other. Authorities should keep digging until they uncover how this mini-terror cell came about.