Europe's cherished system of borderless travel is increasingly at risk as countries grapple with record numbers of refugees and migrants clamoring to enter their territory, officials and analysts say.

German Chancellor Angela Merkel issued an unusually sober warning this week that the passport-free Schengen zone of 26 countries -- hailed as a European success story -- was under threat.

Anti-government demonstrators in Lebanon have staged three large rallies in the past two weeks and a small group Tuesday stormed the environment ministry to press demands for reform. Here's a look at what's behind the protests, the most significant public expression of frustration with Lebanon's dysfunctional system of government in years.

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The killing of a former Irish Republican Army militant has revived fears that the notorious paramilitary group is still operating in secret and has shaken Northern Ireland's fragile power-sharing government.

Seventeen years after the Good Friday peace agreement ended three decades of largely sectarian strife, Kevin McGuigan's murder on August 13 has been widely seen as score-settling within paramilitary ranks.

Less than five months after the last legislative elections, Turks on November 1 will vote again in one of the biggest gambles of President Recep Tayyip Erdogan's political career. 

But the outcome of the snap election, analysts say, risks being exactly the same as in the last polls on June 7. 

Jihadists occupying the Iraqi town of Sinjar are so close that Kurdish fighters can watch them without binoculars and battles are often fought with hand grenades.

Yet eight months after Kurdish forces retook Mount Sinjar from the Islamic State group, the recapture of the nearby town -- the ancestral hub of the Yazidi minority, which has been brutally targeted by IS -- remains a distant prospect.

Billionaire Donald Trump has soared in opinion polls for the Republican presidential primary, but inflammatory anti-immigrant rhetoric could cost him the crucial Latino vote in the 2016 White House race.

"What Trump is doing is political suicide," says Patricio Zamorano, executive director of the consulting firm Infoamericas.info.

It has become a familiar scene in Turkey over the past month. Another soldier is laid to rest, parents grieving as the coffin is draped with the Turkish flag under the merciless glare of television cameras.

Some 60 members of the Turkish security forces have been killed over the past five weeks as the Kurdistan Workers Party (PKK) has hit back at a relentless government air and ground campaign, in the most significant losses sustained by the military and police in recent years.

After escaping a devastating war, frustrated Syrian refugees in aid-starved neighboring states say they must now choose between joining an exodus to Europe or "returning home to die".

Millions of Syrians have found shelter in surrounding countries including Lebanon, Turkey and Jordan that are now struggling to cope with the massive influx.

The Islamic State group had ambitious plans for Afghanistan, but Taliban resistance, U.S. drone strikes, and a society less scarred by sectarianism mean the extremists have so far failed to repeat their Middle Eastern breakthrough.

The jihadist group, which controls large areas of Syria and Iraq, has been trying for months to establish itself in Afghanistan's eastern badlands, challenging the Taliban on their own turf.

As migrants by the thousands pour daily into Hungary, the government is hastily building a barrier along its 174-kilometer (109-mile) border with Serbia: three layers of razor wire and a 4-meter (13-foot) high fence. The migrants, however, are just climbing over the razor wire or crawling under it.

Here's a look at current and historic border barriers, an approach that has been taken for centuries with varying degrees of success.