A Kosovan-born gunman who killed his ex-girlfriend and four other people in a New Year's Eve rampage in Finland shot his victims systematically and did not fire at random, police said.

Finland's third shooting spree in as many years has shocked many. Mourners placed candles outside the shopping centre where four of the five murders took place and huddled outside in icy conditions.

Police said Ibrahim Shkupolli, 43, used an unlicensed handgun to kill three men and a woman at the Sello mall in Espoo, a town near Helsinki, as shoppers stocked up for the New Year holiday.

Shkupolli killed his ex-girlfriend, who had worked at the mall, in an apartment before killing himself at his own home.

"We don't know if the shooter knew the victims (in the shopping centre) beforehand. We are looking into that," Detective Superintendent Esa Gronlund told a news conference.

"At this point, we cannot say why they were shot."

But Gronlund, who is leading the investigation, said Shkupolli was systematic in the way he shot the victims at the mall. "The shootings have taken place in a way that you cannot call them random," he said.

Police said it appeared that Shkupolli was acting alone.

Shkupolli's manager at a logistics company told Finnish news agency STT he was a friendly man but did not discuss his private life at work. The manager described Shkupolli as an upright person and said he was shocked by the news.

STT also reported Shkupolli came to Finland in 1990 but was not granted citizenship because of a criminal record, according to information it received from the Ministry of the Interior.

Gun controls

The shootings have prompted more national soul-searching over Finland's gun control laws, which had already been tightened after two school shootings in 2007 and 2008.

"It is shocking that these kind of things happen so often," said Minna Paananen, a woman in her 40s who welled up with tears as she spoke outside the mall. "I am not scared for myself, but I have a 16-year-old son and I cannot lock him up."

Finland, which has an active hunting community, has the world's third-highest per capita gun ownership, according to the Graduate Institute of International Studies in Geneva.

Prime Minister Matti Vanhanen, in a statement on Thursday, drew attention to the high number of handguns in Finland and said police would focus on how the gunman had obtained his weapon.

Gronlund said he could not say if the ex-girlfriend was killed before or after the other victims.

Using closed circuit television and other evidence, police pieced together the path that Shkupolli took as he stalked the mall. Footage has not been released.

Police confirmed that Shkupolli was previously known to them and that a restraining order had been placed on him to stay away from his ex-girlfriend.

He violated the terms of the order in mid-November, attempting to phone her and sending her a text message. Police said there was nothing threatening in the contents of that message. – Reuters