ADEN, Yemen (AP) -- A celebration by thousands of Yemenis marking the first anniversary of the country's presidential election was interrupted by a shootout on Thursday between government forces and disgruntled members of a southern independence movement, officials said.
Two separatists were killed in the clash that began as President Abed Rabbo Mansour Hadi's supporters gathered in the main square of the city of Aden on Yemen's southwest coast to send a message that the central government is in control of southern Yemen after years of lawlessness.
The demonstrators carried Hadi's posters and marked his one-candidate referendum. The vote drew an end to a yearlong uprising that ousted the longtime autocratic rule of Ali Abdullah Saleh. Saleh stepped down as part of U.S.-backed power transfer deal that gave him immunity from prosecution.
"With dialogue we will correct the path," read signs carried by demonstrators whose rally was broadcast live on state TV.
Wahid Ali Rashed, the governor of Aden, told the gathering: "We have said it a million times before that unity will continue."
But that sentiment not shared by a strong majority of southerners who want to separate from the north after what they say are years of discrimination. And the shooting showed the limits of the government's ability to practice its authority, which continues to be challenged by the armed faction of the separatist movement.
Officials said the armed separatists tried to storm the pro-government demonstration, prompting security forces to open fire. Gunfire was heard across the city, witnesses and officials said. The wounded included four Yemini soldiers, according to the officials, who spoke on condition of anonymity because they were not authorized to speak to the media.
The London-based Amnesty International warned authorities against using violence.
"The Yemeni authorities must end the routine violent repression of freedom of assembly," the group said in a statement issued late Wednesday.
"The Southern Movement and its followers have a right to protest peacefully, and the Yemeni authorities must allow them this right," said Ann Harrison, an official with the group. It referred to incidents in the past when security forces opened what Amnesty described as "indiscriminate fire" on protesters last week, killing two people, including a girl.
Since taking over, Hadi, who is from the south, has tried to unite country. He has carried out a shake-up of the divided military, removing Saleh's relatives and loyalists from senior positions and leading a U.S.-backed campaign against al-Qaida militants in the south. He has also pushed for a national dialogue that would include all rival political and social groups.
Mounting separatist sentiment in the south, however, remains a key challenge for the president. The region was an independent state until it was unified with the north in 1990.
Under Saleh's autocratic rule, the south suffered years of discrimination and unfair distribution of resources. Most southern Yemenis are believed to back an autonomous state, but they are not in favor of armed militias within the separatist movement and do not back an armed fight against government troops.
"Unity has failed and a new political system must be established," said Yassin Said Noaman, a top leader of Yemen's Socialist Party, one of the largest in parliament.
He added that unity has only led to marginalization of the south and that as long as Hadi struggles with other issues, he will not be able to hold the country together and "alienation will continue."
The separatists in the south are also deeply divided, with different factions disagreeing on how to deal with the central government in the capital, Sanaa.
One of the southern leaders, former Interior Minister Mohammed Ali Ahmed, says he welcomes national dialogue but needs guarantees that any deal would eventually be implemented. Others, such as the former vice president Ali Salim al-Beidh, who leads a more militant wing, reject national dialogue. Al-Beidh, who now lives in exile, fled Yemen after a 1994 attempt to declare independence of the south failed, sparking civil war.
The U.N. Security Council warned al-Beidh last Friday of sanctions if he continued to interfere in Yemen's democratic transition. The warning came after al-Beidh was accused of receiving funds from Iran and integrating former al-Qaida members into his movement.
Last month, Yemen's navy seized a ship loaded with a wide variety of Iranian-made weapons, including missiles and rockets. The government in Sanaa asked the U.N. to investigate while Iran, the region's main Shiite powerhouse, denied involvement. For years, Yemen has been fighting Shiite Muslim insurgents near the country's border with Saudi Arabia.
On Thursday, Hadi in an apparent reference to Iran accused a "regional country" of trying to cause instability in southern Yemen.
"A regional country is offering money for extremist factions in the southern movement to use violence and force to foil national dialogue," Hadi said in remarks carried by state TV. He said the only way for southerners to make their demands heard was through national dialogue.
The first session for dialogue is scheduled for March 18.
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