Beji Caid Essebsi has won Tunisia's first free presidential election, beating rival and incumbent Moncef Marzouki with 55.68 percent of the vote, official results show.

Marzouki secured 44.32 percent of the vote, Tunisia's High Electoral Commission said on Monday.

In a Facebook post, Marzouki conceded defeat and congratulated Essebsi on winning the election,

Sunday's presidential run-off vote marked the final step in the country's transition to full democracy, four years after an uprising toppled long-time leader Zine El Abidine Ben Ali.

Essebsi, 88, was a former official in Ben Ali's one-party administration, but reinvented himself as a technocrat and his secular Nidaa Tounes (Call for Tunisia) party profited from the backlash against the country's first post-revolt Islamist government.

Notes From The Field: Al Jazeera's Jamal ElShayyal In Tunis. Tunisians are more concerend than they are excited because there is a relative unknown factor as to what would happen after an Essebsi win. The country has become more and more polarised over the past couple of years because it is a relatively new thing in the Arab world, particularly in Tunisia, to have the freedom of expression and to mobilise politically. People are worried that with Essebsi winning, because of his connections to the old regime and the fact that many in his political party served under Ben Ali, there will be a regression in democracy and progressiveness here in Tunisia. So far, however, Tunisia has managed to exemplify how democracy works post-Arab Spring if one compares it to Egypt, Libya or Syria. So while there are concerns, there is still some hope.

Earlier on Monday, police fired teargas in the southern city of Hamma to disperse hundreds of youths who burned tyres and blocked streets to demonstrate against Essebsi who had declared he had won Sunday's presidential vote, residents said.

"All shops are closed. They are chanting 'No to the old regime'," said Ammar Giloufi, a local resident.

Soon after polls closed on Sunday night, Essebsi, quickly announced that he had won by a clear margin and jubilant supporters took to the streets of the capital in celebration, chanting "Beji President!"

Voting was largely pronounced free and fair with a turnout rate of 60.11 percent, less than the nearly 70 percent in the previous round and legislative elections in October.

Essebsi's victory will enable him to consolidate power, with his new secular party already controlling parliament after defeating the main Islamist party in legislative elections in October.

"I dedicate my victory to the martyrs of Tunisia. I thank Marzouki, and now we should work together without excluding anyone," Essebsi told local television.

The landmark second-round vote sets Tunisia apart from the turmoil of other Arab countries that went through uprisings that started in 2011 and were known by some as "the Arab Spring".

The election was held amid tight security and the closure of main border posts with strife-torn neighbour Libya and is considered Tunisia's first free presidential election since independence from France in 1956.

Essebsi, who was the early favourite after taking 39 percent of the vote in last month's first round, has promised to restore the "prestige of the state'' after unrest and economic problems marked the years since the uprising.

"I voted for Beji Essebsi, because he has a lot of experience, and we have a lot of faith in him that he will fix the country," one supporter told Al Jazeera.

Marzouki, who took 33 percent of the vote last month, had warned that Essebsi, whose party also won October's parliamentary election, would bring back the authoritarian policies of previous regimes.

Tunisia's moderate Islamists, who still have a great deal of backing in the country, did not officially back either candidate, but were believed to lean towards Marzouki.