TUNIS, Sept 26 (Reuters) - Several thousand demonstrators rallied in the Tunisian capital on Sunday to protest against President Kais Saied"s seizure of power, calling on him to step down in the biggest show of public anger since his intervention. Saied this week brushed aside much of the 2014 constitution, giving himself power to rule by decree two months after he sacked the prime minister, suspended parliament and assumed executive authority. "The people want the fall of the coup," chanted the crowd on Tunis"s Habib Bourguiba Avenue, a focal point of the demonstrations that ended the rule of former President Zine El Abidine Ben Ali on January 14, 2011. "Step down." Police maintained a heavy presence around the demonstration and set up barricades. The crisis has endangered the democratic gains that Tunisians won in the 2011 revolution that triggered the Arab Spring protests and has slowed efforts to tackle an urgent threat to public finances. Saied has said his actions, which his opponents have called a coup, are needed to address a crisis of political paralysis, economic stagnation and a poor response to the coronavirus pandemic. He has promised to uphold rights and not become a dictator. Nadia Ben Salem said she travelled 500 km (310 miles)from the south to express her anger. "We will protect democracy...the constitution is a red line," she said, holding up a copy of the constitution. SUPPORT FOR SAIED Saied still has wide support among many Tunisians who are tired of corruption and poor public services and say his hands are clean. Dozens of his supporters appeared at the demonstration. Police separated the two camps. Demonstrators carry flags and banners during a protest against the Tunisian President Kais Saied"s seizure of governing powers. REUTERS/Zoubeir Souissi Demonstrators carry flags during a protest against Tunisian President Kais Saied"s seizure of governing powers, in Tunis, Tunisia, September 26, 2021. REUTERS/Zoubeir Souissi Demonstrators carry flags and banners during a protest against the Tunisian President Kais Saied"s seizure of governing powers. REUTERS/Zoubeir Souissi 1/2 Demonstrators carry flags during a protest against Tunisian President Kais Saied"s seizure of governing powers, in Tunis, Tunisia, September 26, 2021. REUTERS/Zoubeir Souissi "We support Saied because he declared war against a corrupt political class," said a man who would only give his first name, Ahmed. Saied has not put any time limit on his seizure of power, but said he would appoint a committee to help draft amendments to the 2014 constitution and establish "a true democracy in which the people are truly sovereign". Teacher Abdelfattah Saied said it was time for the president to go. "He is acting like he is the sun that is rising on the country, the general prosecutor, the president, the parliament, the government. Like he is everything." Political analyst Slaheddine Jourchi said the protest was a clear escalation against the president and that there was a risk of further divisions among Tunisians if the doors of political dialogue remained closed. Tunisia"s largest political party, the moderate Islamist Ennahda, called for people to unite and defend democracy in "a tireless, peaceful struggle". Ennahda has been the most powerful party in Tunisia since the 2011 revolution that led to the ousting of Ben Ali, playing a role in backing successive coalition governments. But Saied"s actions have left it facing a split. More than 100 prominent officials of Ennahda, including lawmakers and former ministers, resigned on Saturday in protest at the leadership"s performance. After the intervention, Saudi Arabia, the United Arab Emirates and Egypt, which have long mistrusted Islamists across the Middle East, indicated their support for Saied. Tunisia"s influential labour union on Friday rejected key elements of Saied"s actions and warned of a threat to democracy. The first protest against Saied since his intervention on July 25 took place last week.