ADEN - President Abdrabuh Mansur Hadi said Monday that dialogue was the only way to solve Yemen's problems, as violence marred the third day of his visit to the south where security forces clashed with activists. Hadi arrived Saturday on a surprise visit to the south, his first since becoming president in February 2012. On Monday he met officials in Aden as four protesters were wounded when police opened fire to disperse a demonstration in the southeastern city of Mukalla, reports and witnesses said. "Dialogue is the only way to solve all pending issues," Hadi told the officials, the state news agency Saba said. The national dialogue is stipulated in the UN-backed Gulf initiative that eased former president Ali Abdullah Saleh out of office after more than three decades in power. It is scheduled to convene on March 18 and aims at drafting a new constitution and electoral law for parliamentary and presidential polls in 2014. But hardliners in the south have refused to take part in the dialogue and have called for civil disobedience, insisting on a secession of the regions of the formerly independent south. "There are many good forces that want dialogue. But there are also people with narrow interests that do not want dialogue," and are based in Beirut, Hadi said, in reference to exiled leader Salem Baid who heads a hardline faction within the Southern Movement. Most other factions of the Southern Movement have agreed to take part in the dialogue. Protesters, meanwhile, blocked roads in Aden and Mukalla forcing shops and schools to close, witnesses said.