Bloody start to festive period
Cities around the world hit by brutal attacks
In Berlin, a man ploughed a lorry into a crowd at a Christmas market festival, killing 12 people and injuring 48, on Monday evening.
A Pakistani man who was seeking asylum in Germany has been arrested, but it was not clear at press time whether he was the driver of the lorry.
The same night in Ankara, Turkey, the Russian ambassador was shot dead by an off-duty policeman who blamed Moscow for the crisis in Aleppo, Syria.
The gunman was later shot dead.
Shots were also fired outside the US embassy in the Turkish capital, prompting it to close.
And in Zurich, Switzerland, three people were injured when a gunman started shooting inside a Muslim prayer hall.
It may still be five days to Christmas, but the incidents have been a bloody start to the festive period.
It seems that for terrorists or lone wolves out to wreak havoc, the Christmas and New Year period is the killing season.
From the perspective of the people, everyone is winding down for Christmas. Home Affairs Minister K. Shanmugam, earlier this month
Large crowds at shopping precincts, outdoor activities or transport hubs make easy targets, especially when people are preoccupied with the impending festivities.
Home Affairs Minister K. Shanmugam said as much earlier this month when he warned Singaporeans to be vigilant against the threat of terror attacks during the festive period.
"From the perspective of the people, everyone is winding down for Christmas," he said.
"It is safe to say that trying to get our population to understand and realise what we are up against is very much a work in progress that has got a long way to go," he said.
Mr Shanmugam had pointed to a series of actions that could indicate a looming threat, including an uptick in terrorism-related arrests in Indonesia.
On Monday, before the incidents in Europe, the police here said there would be greater police presence and increased checks on bags during this period.
Security companies here also told The Straits Times in a report today about rising demand for their services from shopping malls, event organisers and attractions, compared to last year.
These firms have recruited part-time officers to boost the workforce to meet demand.
In the Berlin attack, a Polish man was later found dead in the lorry.
He is believed to have been killed by the man who later used his lorry to commit mass murder at the market.
The attack, which has been condemned by world leaders, has sparked other countries to step up their security.
In the UK, the police are reviewing their security plans and remain on high alert. The threat level in London remains at "severe", with the police considering an attack highly likely.
Singaporeans who have yet to raise their vigilance might want to heed the words of a German security guard who witnessed the senseless killings: "This is the worst-case scenario and sends a message to the world: It happens everywhere.