On alert since Paris attacks

Danish media said El-Hussein had been jailed for stabbing a 19-year-old man in the leg on a Copenhagen train in 2013, and was freed a few weeks ago.

Danish authorities have been on alert since Islamist gunmen killed 17 people in three days of violence in Paris in January that began with an attack on weekly Charlie Hebdo, long known for its acerbic cartoons on Islam, other religions and politicians.

"Denmark and France are the same nations, feeling the same sadness but also the same will to resist, fight and defeat terrorism," French President Francois Hollande said.

"They hit the same targets, they hit what we are, what we represent, the values of freedom, the rule of law, that all citizens, whatever their religion, should be able to enjoy."

Madsen said the attacks appeared to have been inspired by the Paris attacks.

But police said they did not believe the suspect had received training in jihadist camps in the Middle East.

The man had two handguns on him when he was killed and the police search later found an automatic weapon that may have been used in Saturday's attacks.

The gunman's primary target was likely to have been the free speech event with Vilks.

Dozens of bullets were fired in quick succession, probably from an automatic weapon, according to a recording of the event obtained by Danish TV2.

Prime Minister Helle Thorning-Schmidt said the attacks were terrorism but said this was not the start of a war between the West and Islam.

"When you mercilessly fire deadly bullets at innocent people taking part in a debate, when you attack the Jewish community, you attack our democracy," Thorning-Schmidt said outside the synagogue. "We will do everything possible to protect our Jewish community."