Democratic presidential hopeful Hillary Clinton on Friday condemned Donald Trump's comments that Muslims in America should be registered in a data base.

Trump, leading the polls for the Republican nomination, has issued several controversial remarks about Muslims and Syrian refugees in the wake of last week's attacks in Paris claimed by the Islamic State extremist group.

The European Union agreed Friday to rush through reforms to the passport-free Schengen zone by the end of the year amid growing concerns about border security in the wake of the Paris attacks.

French Interior Minister Bernard Cazeneuve announced the plan as he and his EU counterparts agreed in crisis talks to "immediately" tighten checks on Schengen's external borders while they wait for deeper changes.

United Nations peacekeepers have a responsibility to protect civilians where they are deployed even if that means using force, the U.S. envoy to the world body said Friday during a visit to India, one of the biggest troop contributors.

Samantha Power said U.N. peacekeepers could not "simply stand by as atrocities are committed," as many had in the past, and that a failure to act had likely led to thousands of civilian deaths.

Russian President Vladimir Putin will meet Iran's supreme leader Ayatollah Ali Khamenei during a visit to Tehran Monday, the Kremlin said, as Moscow goes on a diplomatic push over the Syria conflict. 

Talks with Iran's leadership will focus on "issues in bilateral relations, including atomic energy, oil and gas and military-technical cooperation", Putin's top foreign policy aide Yury Ushakov said Friday, with the Russian president also set to meet his counterpart Hassan Rouhani. 

The United Nations on Friday slammed Thailand's deportation of two Chinese refugees, and Vietnam's reported transfer of nine North Korean nationals to China, warning they were at risk of "grave human rights violations."

Ravina Shamdasani, spokeswoman for the U.N. human rights agency, told reporters that Thai authorities had, for unknown reasons, deported two recognized Chinese refugees who had been due for resettlement in a third country.

Turkey summoned the Russian ambassador after Moscow's war planes carried out a heavy bombing raid inside Syrian territory "very close" to the Turkish border, the foreign ministry said on Friday.

Russian ambassador Andrey Karlov was summoned to hear Turkey's concern over Russia's bombing of "civilian Turkmen villages... very close to the border" with Turkey, the foreign ministry said in a statement. 

The United Nations warned Friday that tightening restrictions imposed by countries along the migrant route through the Balkans is creating an increasingly untenable situation, stranding many outdoors amid plunging temperatures.

Hundreds of thousands of migrants -- most of them refugees fleeing conflict and violence in places like Syria, Afghanistan and Iraq -- have crossed the Mediterranean into Europe this year and traveled up from Greece through the Balkans, aiming to start new lives in more prosperous northern European countries.

Unknown gunmen killed four paramilitary soldiers as they guarded a mosque in Pakistan's volatile megacity of Karachi Friday, officials said.

The killers, on three motorcycles, opened fire on the paramilitary Rangers outside the Abu Hurairah mosque in Ittehad Town, a western suburb of the southern city that is infested with Taliban-linked militants.

An African regional bloc has pulled its headquarters out of crisis-hit Burundi after months of violence to ensure the "safety and security of its staff," it said in a statement.

"The situation in Burundi is seriously worrying," the 12-nation International Conference on the Great Lakes Region (ICGLR) said in a statement seen Friday.

EU ministers agreed Friday to get tough on border security after the devastating Paris attacks, as prosecutors said a third body had been found following a police raid on the ringleader's hideout.

Adding to fears about the global jihadist threat, gunmen seized 170 people in a hotel used by foreigners in the capital of Mali, with at least three hostages killed.