Europe was on high alert today as countries tightened their security in the wake of the deadly terror attacks in Paris.

In a sign of the nervousness gripping the continent, Copenhagen Airport was evacuated this morning while Germany's international fixture with Holland last night was called off.

At the Vatican, children, pensioners and even nuns were being searched ahead of the Pope's weekly general audience.

Security has been stepped up after gunmen and suicide bombers went on the rampage in Paris, killing 129 in a wave of attacks on the Stade de France, bars and restaurants and the Bataclan theatre.

In London earlier today, Tooting Broadway tube station was evacuated by police following a security alert.

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Emergency: Tooting Broadway tube station in London was evacuated by police following a security alert earlier this afternoon

Alert: Copenhagen Airport's Terminal 3 was briefly evacuated because of a suspicious bag and a bomb squad (pictured) was called

Police forces secure the the HDI Arena in Hanover after a suspicious package was found inside the ground

Italian Carabinieri officers check a nun as she arrives to attend Pope Francis' Wednesday general audience in Saint Peter's square

Heavily armed police evacuated the line, after receiving reports of a man on the train threatening people with a pair of scissors.

Officers swarmed the underground station and passengers were ordered off a train while they searched for a man matching the description. But no one was found and the incident was stood down.

A Scotland Yard spokesman said: 'Police were called at around 12:50pm today to reports of a man, reportedly armed with scissors, threatening passengers on a train bound for Tooting Broadway underground station.

'Officers, included armed officers, attend Tooting Broadway station and a search of the area was carried out but no-one matching the description of the man was found.

'Armed officers have been stood down, but local officers remain in the area.'

This morning, Copenhagen Airport's Terminal 3 was briefly evacuated because of a suspicious bag - but returned to normal after it was found to be a false alarm.

The terminal was cleared after some passengers reported hearing other passengers talking about a bomb, police said on Twitter without giving details.

No flights were cancelled as departures and arrivals were moved to other terminals of the Nordic region's largest airport.

Alert: Military police soldiers patrol Brussels Airport; Belgium's national security level has been raised to three following the Paris attacks

Officers swarmed the underground station and passengers were ordered off a train. But no one was found and the incident was stood down

Copenhagen Airport's Terminal 3 was cleared after some passengers reported hearing other passengers talking about a bomb, police said on Twitter without giving details

No flights were cancelled as departures and arrivals were moved to other terminals of the Nordic region's largest airport

Danish police said they had increased their security readiness to the second-highest of five levels of readiness, as a consequence of the attacks in Paris last week.

Last night, Germany's friendly against Holland was cancelled just 90 minutes before kick-off following the threat of an attack at the stadium.

Police chief Volker Kluwe said there had been 'a concrete threat scenario for all of Hanover' and that there had been 'serious plans to cause an explosion'.

He added that a device was intended to be detonated inside the HDI Arena which has a capacity of 45,000.

The postponement comes just four days after Germany's match against France in Paris was targeted by terrorists as part of a coordinated attack on the capital which killed 129 people. One bystander was killed and several more injured while 79,000 supporters watched the match in the ground.

Meanwhile, Italian police were seen searching bags and using electronic scanning devices this morning as crowds arrived at the Vatican's St Peter's square.

Pope Francis used his speech today to say that the doors of Catholic churches around the world must remain open, despite increased security fears in the aftermath of the Paris attacks.

A bride and groom arriving for the general audience were not exempt from the checks carried out today

Spot check: A boy holds his arms out while a security guard uses an electric scanning device

Francis's comments also had a spiritual significance - he has urged the Church to keep its doors open to lapsed believers who are considering returning

Check point: Visitors were asked to pass their belongings through a scanner ahead of the speech today

Armed response: A police officer with a gun stands on guard at St Peter's Square amid heightened security

His comments came in the context of intense discussion in Italy about the security of the Vatican and Rome, which are seen as potential targets for Islamist militants.

'Please, no armoured doors in the Church, everything open,' the 78-year-old pontiff told pilgrims in St Peter's square, Italy's AGI news agency reported.

'There are places in the world where doors should not be locked with a key. There are still some but there are also many where armoured doors have become the norm.

'We must not surrender to the idea that we must apply this way of thinking to every aspect of our lives, ...' Francis said.

'To do so to the Church would be terrible.'

The pope did not explicitly refer to last week's attacks on Paris, which he has condemned as 'inhuman'.

Francis's comments also had a spiritual significance - he has urged the Church to keep its doors open to lapsed believers who are considering returning and to the hundreds of thousands of migrants arriving in Europe from Africa, the Middle East and South Asia.

Italy announced this week that it would close airspace over Rome to drones for the duration of the upcoming Catholic jubilee year, which is expected to bring more than a million extra visitors to the Italian capital.

Police stopped and searched bags as people made their way towards a security checkpoint

Italy announced this week that it would close airspace over Rome to drones for the duration of the upcoming Catholic jubilee year,

Pope Francis used his speech today to say that the doors of Catholic churches around the world must remain open, despite increased security fears in the aftermath of the Paris attacks

The move reflects fears a remote-controlled aircraft could be used by Islamic State or other militant groups to stage a potentially spectacular attack on the home of the Catholic church.

Security has also been stepped up at airports and train stations and some 700 extra troops deployed in public spaces in Rome.

Individuals purporting to be Islamic State militants have made a number of threats against Rome on social media and in the group's propaganda outlets.

Italian officials say they take such statements seriously but that they have never received evidence of a credible, specific plot to bomb Rome, the Vatican or the Pope.

Over the weekend, Pope Francis revealed he was 'shaken' by what he described as the 'inhuman' attacks on a string of Paris venues which left at least 129 people dead.

The pontiff said there could be 'no justification, religious or human' for the massacre in the French capital last night.