* Douma suffered deadly chemical weapons strike in 2018
* Assad says no weight to Western nations' opinions
* Protests in rebel Idlib; Kurdish authority closes border (Adds polls close at midnight para 9)
By Suleiman Al-Khalidi and Maha El Dahan
AMMAN, May 26 (Reuters) - Syrian President Bashar al-Assad voted on Wednesday in an election certain to extend his rule over a country ruined by war, casting his ballot in an ex-rebel bastion where a suspected chemical weapons attack in 2018 prompted Western air strikes.
The government says the election shows Syria is functioning normally despite the decade-old conflict, which has killed hundreds of thousands of people and driven 11 million people - about half the population - from their homes.
"Syria is not what they were trying to market, one city against the other and sect against the other or civil war. Today we are proving from Douma that the Syrian people are one," Assad said after voting in the former insurgent stronghold.
However, in the southern city of Deraa, cradle of the uprising against Assad in 2011 and an opposition redoubt until rebels there surrendered three years ago, local leaders called for a strike.
The election went ahead despite a U.N.-led peace process that had called for voting under international supervision that would help pave the way for a new constitution and a political settlement.
Dismissed as fraudulent by his enemies, Wednesday's vote is set to deliver Assad seven more years in power and lengthen his family's rule to nearly six decades. His father Hafez al-Assad led Syria for 30 years until his death in 2000.
The opposition boycotted the vote and said Assad's presidential rivals were deliberately low-key: former deputy cabinet minister Abdallah Saloum Abdallah and Mahmoud Ahmed Marei, head of a small, officially sanctioned opposition party.
Addressing his critics, Assad said Syrians had made their feelings clear by coming out in large numbers. "The value of your opinions is zero," he said.
Polls closed at midnight after authorities extended voting by five hours due to the high turnout.
At Damascus University's Faculty of Arts, hundreds of students lined up to vote, with several buses parked outside.
"With our blood and soul we sacrifice our lives for you Bashar," groups of them chanted before the polls opened, in scenes repeated across the 70% of Syria now under government control.
"We came to elect President Bashar al-Assad...Without him Syria would not be Syria," said Amal, a nursing student, who declined to give a second name for fear of reprisals.
Officials said privately that authorities had organised large rallies in recent days to encourage voting, and the security apparatus that underpins Assad's Alawite minority-dominated rule had instructed state employees to vote.
"We have been told we have to go to the polls or bear responsibility for not voting," said Jafaar, a government employee in Latakia who gave his first name only, also fearing reprisals.
DAY OF ANGER
Douma, where Assad voted, is a Sunni Muslim town in the Eastern Ghouta region on the outskirts of the capital Damascus. It was long a focus of defiance against Assad's rule until it was retaken after years of siege and bombing that killed thousands of civilians.
A suspected chemical attack in 2018 killed at least 50 civilians, one of several - mainly in the Ghouta area - that left hundreds dead. The United States, France and Britain responded with air strikes on suspected chemical weapons sites.
"Assad wants to send a message that Douma, one of the first areas that fell out of his control, is today secure and safe to cover up the election farce," said Wael Alwan, a researcher from Douma who now works at Istanbul's Syrian Jusoor think-tank.
Sulaiman, a former militiaman who battled the rebels in Ghouta when they threatened Assad's hold over Damascus early in the conflict, described Assad's vote as "a final declaration of victory" against Islamist militants.
In parts of Deraa in the far south, local figures called for a general strike to vent their opposition to the election.
Former rebels in the area said there were several incidents of gunfire against vehicles carrying ballot boxes, and shops in many towns were closed.
"All people reject the rule of the son of Hafez," read graffiti scribbled across several towns in the south, the last part of the country to fall to Assad under Russian-brokered agreements, where former rebels still resist his rule.
There was no voting in the northwestern Idlib region, the last existing rebel enclave where at least three million of those who fled Assad's bombing campaign are sheltering, people took to the streets to denounce the election "theatre".
"It's a day of anger, let's participate and raise our voices in the squares of freedom to announce our rejection of the criminal Assad and his elections," said one of the posters hung in a rebel-held town along the border with Turkey.
In the northeast, where U.S.-backed Kurdish-led forces administer an autonomous oil-rich region, officials closed border crossings with government-held areas to prevent people from heading to polling stations.
They said the election was a setback to reconciliation with a Kurdish minority that has faced decades of discrimination from one-party rule and Arab nationalist ideology.
(Reporting by Suleiman al-Khalidi with additional reporting by Rodi Said in Qamishli and Khalil Ashawi in Idlib Writing By Maha El Dahan Editing by Dominic Evans and Mark Heinrich)
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