Key dates in Yemen since a transition accord was signed by the regime and the opposition in November 2011 calling for a national dialogue, which started on March 2013.
The accord, signed in Riyadh following an 11-month popular revolt in which hundreds of people were killed, resulted in president Ali Abdullah Saleh's ouster after 33 years in power and his replacement by his deputy Abdrabuh Mansur Hadi.
November 23: Saleh signs a deal with the parliamentary opposition, drawn up by Gulf monarchies, to transfer power to Hadi, in exchange for immunity from prosecution for him and his family.
The accord also provides for a national dialogue aimed at drawing up a new constitution and preparing for legislative and presidential elections which are due to take place in February 2014.
February 25: Hadi sworn in days after receiving, as sole candidate, 99.8 percent of valid votes.
The ceremony is overshadowed by a suicide bombing, claimed by al-Qaeda, which kills 25 troops in the southeast.
February 27: Saleh formally steps down.
March 4: 185 soldiers and at least 25 suspected al-Qaeda gunmen killed in the south.
April 9-14: More than 220 killed in clashes between the army and al-Qaeda.
May 12-mid-June: The army begins a major offensive to retake the cities of Zinjibar, Jaar and Shaqra from al-Qaeda. More than 560 people are killed.
The United States increases targeted drone strikes against al-Qaeda militants.
May 21: Some 100 soldiers are killed and hundreds more wounded when a suicide bomber blows himself up among them in Sanaa.
Al-Qaeda claims responsibility.
May 31: Yemen's Zaidi Shiite rebels agree to join the national dialogue.
August 14: Troops of Yemen's elite Republican Guard, which is led by the son of Saleh, attack the defence ministry, leaving three people dead.
September 12: In Sanaa, more than 200,000 people demonstrate to demand Saleh's immunity be lifted, accusing him of fuelling violence.
October 3: An alliance of groups that want federalism or full independence for the south of the country - the Southern Movement - says it will boycott the national dialogue.
December 19: Hadi announces a restructuring of the army and defence ministry, removing cronies of Saleh.
January 27: A UN Security Council team pays a rare visit to Sanaa in a clear boost to Hadi.
February 15: The Security Council warns Saleh he could face sanctions for undermining the political transition.
February 21: Unrest intensifies across the south when protesters marking the first anniversary of Saleh's ouster clash with police in Aden.
Nine people are killed in six days.
February 24-25: President Hadi pays his first visit to the south, urging separatists to take part in the national dialogue.
February 27: Saleh rallies his loyalists in Sanaa to reassert his support for Yemen's unity.
March 9: Southern Yemen leaders meeting in Dubai under the auspices of the UN say they are in favour of dialogue and reject violence.
March 17: Thousands of separatists rally in Aden to protest against the national dialogue process, saying that leaders from Southern Yemen have not been included in the process and that their region be allowed to secede from the north.
March 18: Hundreds of representatives from various political groups gather in Sanaa to discuss roadmap under UN-backed deal.
April 11: President Hadi orders the removal of top security officials from government, in a major shake-up directed at allies of ousted president Ali Abdullah Saleh.
April 27: At least five troops killed at checkpoint outside Sanaa, as intelligence chief is shot dead outside his home in Mukalla.
June 8: Yemen begins the second round of its national dialogue in Sanaa as President Hadi hailed progress made in March talks.
June 9: At least seven people have been killed and at least 30 wounded in a gun fight next to the National Security Agency building in Sanaa.
June 12: Houthis, members of Shia group march in capital calling for more say in country's future and new national security service.
June 17: A senior member of Al-Qaeda in the Arabian Peninsula (AQAP) has confirmed that Said al-Shihri, its second-in-command, has been killed in Yemen.
August 3: The United States issues a global travel alert to warn its citizens of potential "terrorist attacks", particularly in the Middle East and North Africa, including Yemen.
August 4: The US temporarily closes 21 embassies and consulates in mostly Muslim countries, and several European states shut embassies in Yemen over fears al-Qaeda was planning to launch attacks.
August 25: At least one person has been killed and dozens injured in a bomb attack on a bus carrying members of Yemeni air force officers in capital Sanaa.
September 20: Dozens are killed in twin attacks on military targets, officials say, with two car bombs exploding at a base in Shabwah and a separate shooting targeting soldiers at a base in Mayfaah.
Source: Al Jazeera