The twin-shooting in Copenhagen, Denmark recently has left the world speechless, which comes about a month after the Charlie Hedboe terror attack.

Denmark held a mass memorial and a rally to honor the victims who died in the attack. The victims include killing a film-maker who was killed, three injured police officers in the first attack and a Jewish man was killed and two police officers wounded near the city's main synagogue, in the second attack, according to The Telegraph.

The Prime Minister, Helle Thorning-Schmidt and other prominent Danish politicians and the leaders of other Scandinavian countries attended the remembrance ceremony in Copenhagen, according to the Daily Mail.

The killer Omar el-Hussein, 22, a Dane of Palestinian descent, was killed by police hours after a second attack. According to BBC, the attacker pretended to be a drunken guest to get past a police cordon, but was stopped by Dan Uzan, a Jewish economist standing outside as a volunteer security guard.

The police have said that they killed the man in the Norrebro district after he opened fire on them, according to BBC.

Uzan, however, didn't survive to tell the story of his brave encounter as he was shot soon after by the gunman.

A day after the attack, a couple of men were charged as the gunman's accomplices. They are being held as suspects who might have helped the Islamist gunman obtain weapons and evade police.

The police, who have been reluctant to up until now to reveal the weapon used in the attacks, have said the weapon used to unleash a barrage of 40 bullets was an M95 automatic rifle, according to a report from court proceedings. Until 2010, the M95 was the automatic rifle of choice for the Danish army, according to BBC. So the question of how the gunman obtained the weapon still remains unanswered.