President Viktor Yanukovych met with opposition political leaders Wednesday evening and announced that they had reached an agreement on a truce to end the fighting that broke out Tuesday and has left at least 26 dead.

The two sides also said they had agreed to resume negotiations toward a settlement. They met after a day that brought signs of turmoil within Yanukovych’s government, including the unexplained dismissal of the chief military commander.

Despite the truce, there were reports of fighting early Thursday morning between protesters and police in Kiev.

The development came as U.S. and European leaders condemned the violence and the United States said it was imposing visa sanctions on 20 Ukrainian officials. Russia, meanwhile, condemned the opposition.

The pressure on Ukraine — internal and external — has only increased, and the two sides are so far apart that reconciliation appears impossible. They are now faced with the challenge of getting the country back on track even without reconciling politically.

The big story

Protests first started in Ukraine on Nov. 21, when President Viktor Yanukovych rejected a deal with the European Union and moved closer to Russia. Violence flared back up again Tuesday after the parliament refused to take up the issue of a new constitution.

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The hostility between Yanukovych and the political opposition is deep and intense, and now has been paid for in blood. Regional differences are flaring, with governors in the east near the Russian border denouncing the protesters and demanding a crackdown, while in the west, cities are declaring virtual autonomy from the central government. Opposition leaders, for their part, are leading a movement that includes hard-line militants who are not keen on political compromise.

Abroad, the Western nations and Russia blamed each other for supporting one of the two sides in Ukraine’s long-running political crisis.

The country, which has experienced regular bouts of political turmoil since the downfall of the Soviet Union two decades ago — but never the sort of violence seen Tuesday — appears to be at a point of fracture.

That may now be extending to the government itself.

As fires continued to burn Wednesday on the Maidan, or Independence Square, forming a buffer of flame and thick greasy smoke between protesters and police, the state security service announced that it was launching an “anti-terrorist operation.” A little while later, the Defense Ministry said it might join in.

It appeared as though a serious escalation was in the works. But then Yanukovych fired his chief military commander Wednesday evening.

Col. Gen. Volodymyr Zamana was quoted a month ago as saying that the armed forces should never be used against Ukrainian civilians, and this may have been the reason for his ouster.

The Ukrainian army is not as well-funded or powerful a force as the Interior Ministry. Nonetheless, it wields heavy weaponry that the opposition fears may come into play.

U.S. military leaders have been unable for the past several days to reach their Ukrainian counterparts to warn them against getting involved in the crisis, a senior U.S. official said Wednesday night, and this is a matter of some concern.

Ukraine’s military has joined with NATO in Iraq and Afghanistan and has particularly close relations with the Polish military. But Poland has been Yanukovych’s most vocal critic, and that may leave him uncertain of his own army’s loyalty in a fight portrayed as East vs. West.

Later in the evening, the security service said that although it was making preparations for an anti-terrorist operation, it had not put one into effect, according to the Interfax news agency.

All this has left Ukrainians wondering whether a crackdown is coming and, if so, how effective it might be given the conflicting pressures on the beleaguered country.

Small but violent protests Wednesday left several people wounded and one reported dead in the Black Sea port of Odessa and in the western city of Khmelnytskyy.

In the east — in Donetsk, Yanukovych’s home town, and Kharkov — governors talked tough about defeating the protests.

But the city of Lviv in western Ukraine effectively declared itself autonomous of the central government. In nearby Ivano-Frankivsk, the local commander of the security forces pledged not to carry out or give any illegal orders.

Obama warns both sides

The Russian Foreign Ministry, which backs Yanukovych, said Tuesday’s violence was an attempted coup by the opposition, and Foreign Minister Sergei Lavrov called on Western countries to use their influence with the opposition to force it into negotiations with the government.

The White House and the European Union strongly criticized Yanukovych earlier Wednesday, blaming him for the violence.

President Obama had warnings for both Yanukovych and protest leaders.

“I want to be very clear as we work through these next several days in Ukraine that we’re going to be watching closely and we expect the Ukrainian government to show restraint, to not resort to violence in dealing with peaceful protesters,” Obama said. “We’ve also said we expect peaceful protesters to remain peaceful, and we’ll be monitoring very closely the situation, recognizing that with our European partners and the international community there will be consequences if people step over the line.”

E.U. Commission President José Manuel Barroso expressed “shock and utter dismay” Wednesday over the “violence and use of excessive force,” which he blamed on Ukraine’s “political leadership.” He said he expects the E.U. to agree on “targeted measures against those responsible.”

The Swedish foreign minister, Carl Bildt, said Yanukovych “has blood on his hands.”

Bildt said Ukraine would have been on its way to a better future by now, with a trade agreement with the E.U., were it not for threats from Moscow.

The foreign ministers of Poland, Germany and France intend to travel here Thursday to hold talks about the crisis and then to Brussels for an E.U. meeting to consider targeted sanctions against Ukrainian officials.

Authorities said that 800 people have been injured, and that of the 26 killed, 10 were Interior Ministry troops.

[READ: Could this become civil war?]

There have been guarded expressions of unease within the ruling Party of Regions over the violence. Ukraine is without a prime minister a month after Mykola Azarov was forced from office. Rinat Akhmetov, an oligarch once very close to Yanu­kovych, has called for an end to violence by both sides.

If an “anti-terrorist” campaign begins, it is not clear what it will entail or how effectively it can be carried out. Government officials say hard-line protesters have stolen 1,500 firearms during the three months of demonstrations and have used them against police.

A special operation would presumably give the security service the authority to seize people and property without court orders for a specified period.

Vice President Biden has warned Yanukovych several times — most recently on Tuesday — against declaring a state of emergency.

The Defense Ministry denied that armored units were moving to Kiev. Paratroop battalions have been deployed to guard Defense Ministry sites, but not to take part in an attack on protesters, officials said.

Focus on rightists

Yanukovych, echoing the Russians, has said that the top political leaders of the opposition must disassociate themselves from the right-wingers among the protesters who have done most of the fighting with police.

Helmeted young militants of the group that calls itself Pravy Sektor have without question complicated the role of more moderate political leaders and, in important ways, have helped set the opposition agenda. Opposition politicians have been careful not to have a falling-out with their most committed wing.

In a joint statement, the three main opposition parties said they were not responsible for Tuesday’s deadly violence.

“We have never called and never will call people to pick up arms,” it said. “This is our principled stance. The death of any person is a personal tragedy for each one of us.”