PARIS -- Tens of thousands of people protested against France's new gay marriage law in central Paris on Sunday, and police clashed with right-wing demonstrators.

The law came into force over a week ago, but organizers decided to go ahead with the long-planned demonstration to show their continued opposition as well as their frustration with President Francois Hollande, who had made legalizing gay marriage one of his keynote campaign pledges in last year's election.

Marchers set off from three separate points across Paris, and by early evening they filled the Invalides esplanade just across the Seine River from the Champs Elysees.

As night fell, several hundred protesters clashed with police, throwing bottles and chasing journalists.

Interior Minister Manuel Valls said police had arrested around 100 far-right protesters who refused to leave following the end of the demonstration.

Meanwhile, in southern France, the 66th Cannes Film Festival gave the Palm d'Or, its top honor, to "Blue is the Warmest Color: The Life of Adele," a French film about a tender, sensual lesbian romance.

Police estimated around 150,000 people took part in the demonstration in Paris, but march organizers claimed on their Twitter account that more than a million people did.

A similar protest in March drew about 300,000.

Around 5,000 police were on duty Sunday because previous anti-gay marriage protests also had seen clashes between far-right protesters and the police.

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  • Netherlands

    The Netherlands was the first country to recognize gay marriage in <a href="http://news.bbc.co.uk/2/hi/4081999.stm" target="_hplink">2001</a>. <em>Pictured: Jan van Breda and Thijs Timmermans.</em>

  • Belgium

    Belgium legalized same-sex marriages in <a href="http://news.bbc.co.uk/2/hi/4081999.stm" target="_hplink">2003. </a> <em>Pictured: Marion Huibrecht and Christel Verswyvelen.</em>

  • Spain

    Spain legalized gay marriage in <a href="http://news.bbc.co.uk/2/hi/4081999.stm" target="_hplink">2005</a>.

  • Canada

    Canada followed Spain and approved gay marriage in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2005. </a>

  • South Africa

    South Africa legalized same sex marriage in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2006.</a> <em>Pictured: Vernon Gibbs and Tony Hall. </em>

  • Norway

    Norway followed suit in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2009.</a> <em>Norwegian finance minister and chairwoman of the Socialist Left party Kristin Halvorsen (L) stands next to wedding figurines outside the House of Parliament in Oslo on June 11, 2008, where she celebrated the passing of a new law awarding equal rights to same sex partnerships as those enjoyed by heterosexual marriages. (Getty)</em>

  • Sweden

    Sweden recognized same sex marriage in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2009.</a> <em>Pictured: Johan Lundqvist (L) and Alf Karlsson. </em>

  • Portugal

    Portugal recognized gay marriage in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2010.</a> <em>Pictured: Teresa Pires and Helena Paixao. </em>

  • Iceland

    Iceland legalized gay marriage in <a href="http://www.bbc.co.uk/news/world-latin-america-10650267" target="_hplink">2010.</a>

  • Argentina

    Argentina legalized same sex-marriage in <a href="http://news.bbc.co.uk/2/hi/4081999.stm" target="_hplink">2010.</a> It was the only Latin American country to do so. <em>Pictured: Giorgio Nocentino (L) and Jaime Zapata.</em>

  • New Zealand

    New Zealand<a href="http://www.huffingtonpost.com/2013/04/17/maurice-williamson-new-zealand-gay-marriage-_n_3100714.html?utm_hp_ref=gay-voices" target="_blank"> became the first</a> Asia-Pacific nation (and the 13th in the world) to legalize same-sex marriage. <em>Pictured: Jills Angus Burney (L) and Deborah Hambly.</em>

  • Denmark

    Denmark became the first country to allow the registration of gay partnerships in 1989. In 2012, Denmark's <a href="http://www.huffingtonpost.com/2012/06/07/denmark-approves-gay-wedd_0_n_1577288.html" target="_blank">Parliament approved </a>a law allowing same-sex couples to get married in formal church weddings instead of the short blessing ceremonies that the state's Lutheran Church offered.

  • Uruguay

    The Uruguay Parliament lawmakers passed the <a href="http://www.huffingtonpost.com/2013/04/10/uruguay-legalizes-gay-marriage_n_3057458.html" target="_blank">"marriage equality project"</a> in Montevideo, Uruguay,Wednesday, April 10, 2013.

  • U.S.A.

    Same-sex marriage is legal in 13 U.S. states and Washington DC.

  • Brazil

    Some <a href="http://www.huffingtonpost.com/2011/10/26/brazils-top-appeals-court-upholds-gay-marriage_n_1032481.html" target="_blank">parts of Brazil</a> allow same-sex marriage (AL, BA, CE, DF, ES, MS, PR, PI, SE, and SP).

  • Mexico

    Some areas of Mexico allow gay marriage, such <a href="http://www.huffingtonpost.com/2012/12/06/mexico-gay-marriage-law-unconstitutional-_n_2249701.html" target="_blank">as Mexico City</a>.

  • France

    France legalized same sex marriage in <a href="http://www.huffingtonpost.com/2013/04/23/france-gay-marriage-law-_n_3139470.html?utm_hp_ref=world&ir=World&utm_hp_ref=world" target="_hplink">2013</a>. Pictures: an illustration made with plastic figurines of men is seen in front of the Palais Bourbon, the seat of the French National Assembly. (JOEL SAGET/Getty Images)

  • Britain

    Britain legalized gay marriage on July 17, 2013 after Queen Elizabeth II gave her royal stamp of approval. Gay marriages are set to begin in England and Wales in the summer of 2014.