Six boiling cauldrons around the world

Protests have turned bloody in Ukraine as violence flared this week in conflicts around the world. 

Egyptian militants launched a deadly attack on a tourist bus in southern Sinai. In Venezuela, opposition leader Leonardo López came out of hiding and surrendered amid protests aimed at the leftist government. The third anniversary of the rebellion that ousted Libyan leader Moammar Gadhafi was punctuated by a bombing.  

Here is a quick guide to several conflicts, and their impact on world politics and markets.

—By CNBC.com
Posted 19 Feb. 2014

With the Olympics being played in neighboring Russia, violence has returned to Kiev's Independence Square, heart of the Ukrainian capital. President Viktor Yanukovich has imposed laws to clamp down on mass demonstrations, which were originally called to protest the country's increasingly close ties with Moscow. 

At least 25 people were killed Tuesday, according to The Associated Press. On Wednesday, the embattled president replaced the armed forces chief and the military announced it could take part in a national anti-terrorist operation to restore order, the AP said.

President Barack Obama on Wednesday warned, "There will be consequences if people step over the line."

"We expect the Ukrainian government to show restraint, to not resort to violence," he said. "We expect peaceful protesters to remain peaceful. We will be monitoring this closely."

The European Union has called an extraordinary meeting of its foreign ministers for Thursday to discuss sanctions against the country. 

Monday marked the third official anniversary of the the start of the uprising that overthrew Gadhafi.  

Crime is rampant, and bombings occur frequently. Libyan militias demanded Tuesday that parliament surrender power immediately. The ongoing protests over the country's political future have disrupted Libya's oil industry, a key driver of its economy.

Oil output dropped to 375,000 barrels a day Tuesday as protests disrupted a pipeline from the important El Sharara field, a National Oil Corp. spokesman told Reuters. Austrian petroleum company OMV reported that it is operating its oil fields in Libya at about 70 percent of normal levels.

Protests have broken out in Caracas over what critics say is an increasingly authoritarian government headed by President Nicolás Maduro.  

The tensions in the country, along with those in Libya, are helping to keep the price of oil high—Brent crude was trading around $110 a barrel on Wednesday.

"Venezuela is for now only under street protests, but those protests are starting to be large and we have to keep in mind that the riots, chaos and deaths in Ukraine also initially started with just street protests," Olivier Jakob, an analyst at Petromatrix, told Reuters. "The Venezuelan risk factor cannot be discounted."

A nearly 3-year-old uprising in Syria is descending further into war, with an al-Qaeda-linked militant group most recently claiming responsibility for two bombings in Beirut via the group's Twitter account on Wednesday.  

Russia, along with China, has vetoed three Western-backed U.N. resolutions aimed at increasing pressure on President Bashar Assad, but the Russian foreign minister said Wednesday the country might agree to a resolution on humanitarian aid in the coming days, Reuters reported.

President Barack Obama is reluctant to use military force to end the fighting. White House spokesman Jay Carney suggested to reporters that the president is reluctant to fight another war in an Islamic country—especially one that may have "unintended consequences."

A suicide bomber from the Egyptian militant group Ansar Beit al-Maqdis killed three South Korean tourists and their Egyptian bus driver in Sinai on Sunday, according to AP, and the group threatened to attack all foreign tourists who remain beyond Thursday. Tourism is a significant portion of the Egyptian economy. The country is receiving funds from Gulf region allies, and investors believe the government can contain the violence, according to Reuters.

Egypt's bourse rose to a five-year high Wednesday after the country's central bank said it would distribute $1.4 billion to commercial banks for mortgage lending, Reuters reported.

The photo at left shows a December 2013 demonstration by supporters of ousted President Mohammed Morsi, a leader of the Muslim Brotherhood.

Iranian government officials met with six other world powers in Vienna to settle the decade-long impasse regarding Iran's nuclear program.   

The United States, Russia, China, Britain, France and Germany want Iran to cap enrichment of uranium, limit new research and new equipment, decommission a substantial portion of its uranium refineries, and allow more thorough U.N. nuclear inspections, according to Reuters.  

Participants say the talks so far are going well, but the Ayatollah Ali Khamenei—Iran's supreme leader—expressed skepticism over their outcome. The Iranian government invited the Austrian president to visit the country, the first of such invitations since President Hassan Rouhani was elected.