The wave of Arab Spring protests that swept across Tunisia, Egypt, Libya and other north African and Middle Eastern countries broke out a year ago in Syria, drawing a deadly crackdown from government forces and pledges of reforms from President Bashar al-Assad. The international community remains divided on how to bring an end to the violence, which United Nations officials estimate has killed 8,000 people.

Here is a timeline of major developments since the protests against Mr. Assad's autocratic rule began:

March 15, 2011: A small group of protesters gather in Old Damascus.

March 16, 2011: Syrian security forces in Damascus break up an opposition protest calling for the release of political prisoners. Some demonstrators are detained.

March 18, 2011: Witnesses say security forces kill three people while dispersing a protest in the southern city of Daraa.

March 24, 2011: The Syrian government announces a series of reforms, including the first suggestion that emergency laws, in place since 1963, might be lifted.

March 29, 2011: The Syrian government resigns, but President Bashar al-Assad remains in power. Rallies in support of the president take place in several cities, including the capital, Damascus.

April 14, 2011: President Assad announces a new 31-member government. He orders the release of detainees arrested in the wave of protests, except those convicted of “criminal acts.”

April 19, 2011: The Syrian government approves an end to emergency laws that ban public demonstrations and restrict the media.

April 22, 2011: Security forces and gunmen loyal to President Bashar al-Assad kill at least 75 protesters, rights group say.

April 29, 2011: The U.S. imposes new sanctions on Syria, targeting its intelligence agency and two relatives of the president.

June 20, 2011: President Assad blames the uprising on “saboteurs” outside the country. In a 70-minute televised speech, he pledges to hold parliamentary elections, work to create new political parties and amend the constitution. But he says he will not implement change amid chaos.

July 7-8, 2011: U.S. Ambassador Robert Ford and French Ambassador Eric Chevallier visit the city of Hama to show support for thousands of protesters there.

July 10, 2011: Syrian opposition members boycott talks with the government to protest the crackdown on demonstrators.

July 15, 2011: A Human Rights Watch official tells VOA that 17,000 people have been detained since March and detention centers are extremely overcrowded. He says his group has documented torture and brutal beatings.

August 7-9, 2011: Saudi Arabia, Kuwait and Bahrain withdraw their ambassadors from Syria. Arab League Secretary General Nabil Elaraby urges Syria to “stop all acts of violence.” Turkish Foreign Minister Ahmet Davutoglu meets with President Assad in Syria to call for an end to the violence.

August 17, 2011: U.N. Secretary-General Ban Ki-moon speaks by telephone with President Assad, saying he is alarmed at reports of excessive use of force by the government and widespread human rights violations. Mr. Ban also calls for an independent investigation of the violence.

August 18, 2011: The United States calls for Mr. Assad's resignation. Secretary of State Hillary Clinton says the transition to democracy in Syria has begun and calls on Mr. Assad to “get out of the way.”

September 2, 2011: The European Union bans oil imports from Syria.

October 5, 2011: Russia and China veto a U.N. Security Council resolution condemning Syria for its brutal crackdown on civilian protesters.

November 12, 2011: The Arab League suspends Syria's activities in the group until President Assad's government implements a peace plan to end violence against protesters. The United Nations says the death toll in Syria exceeds 5,000 people.

December 19, 2011: Syria agrees to an Arab League peace plan and observer mission designed to end the bloody crackdown on protesters.

January 10: Mr. Assad gives a 100-minute address praising the work of his security forces and vowing to crack down on “terrorists” with an “iron hand.” He pledges to hold a constitutional referendum in March and parliamentary elections as soon as May.

January 28: The Arab League suspends its month-old monitoring mission in Syria after an escalation of violence.

February 4, 2012: Russia and China veto a second U.N. Security Council resolution condemning President Assad's crackdown and calling for him step down.

February 22: Shelling by Syrian forces in Homs and elsewhere kills at least 74 people, including American war correspondent Marie Colvin and French photojournalist Remi Ochlik.

February 27: Syria announces voters overwhelmingly approved a new constitution. The opposition and Western countries dismiss the referendum.

March 1: Syrian rebel fighters pull out of the besieged Baba Amr district of Homs after a punishing, month-long military assault by President Bashar al-Assad's security forces.

March 8: Syria's deputy oil minister resigns to join the opposition. He urges his colleagues to abandon what he called a “sinking ship.”

March 10-11: Former U.N. secretary-general Kofi Annan visits Syria for talks with Mr. Assad, but leaves with no resolution to the crisis.

March 14: Forces loyal to Mr. Assad overrun most of the northern city of Idlib. Three prominent members of the opposition Syrian National Council resign.

March 16: Kofi Annan is scheduled to brief the U.N. Security Council.