Sweden's Securitas, the European leader in security services, reported Tuesday a sharp rise in profits for 2015 amid an increased threat of terrorism and the European migrant crisis.

Net profit for the full-year rose by 18 percent to 2.44 billion kronor (258 million euros, $288 million), or eight percent excluding currency effects.

Sales climbed by 15 percent to 80.8 billion kronor.

In Europe, sales rose by eight percent to 37.5 billion for 2015 and by 11 percent in the fourth quarter, bolstered by the November 13 attacks in Paris and the arrival of hundreds of thousands of migrants in Europe.

"The increased need for security services due to terrorism alerts and the refugee situation has impacted organic sales growth in primarily France, Belgium, Germany and Sweden," the group said in its earnings report.

Events in Turkey, a country which has welcomed around two million Syrian refugees on its soil and saw a number of terrorist attacks last year, also contributed to the strong earnings.

However, Securitas' operating margin remained under pressure, at 5.1 percent in 2015 compared to 5.0 percent a year earlier, owing to rising labour costs in Sweden and operational spending.

In North America, Securitas posted sales of 31.1 billion kronor, a rise of 24 percent, which exceeded market expectations.

At 1200 GMT, the Securitas share price was down by 7.0 in an overall market down by 0.5 percent, with fourth quarter earnings coming in below analysts' forecasts.