Dublin, Ireland (CNN) As women around the world wore red in solidarity with International Women's Day, crowds in Ireland donned black and went on strike to protest against the country's restrictive abortion laws.

Traffic ground to a halt in parts of Dublin Wednesday as women and abortion rights activists sang along to Cyndi Lauper's "Girls Just Want to Have Fun" and the Spice Girls' "Wannabe" during a raucous dance party on O'Connell Bridge.

After sundown, a second, separate demonstration -- also in protest against Ireland's abortion laws -- commenced, with Irish police estimating 10,000 to 12,000 people on the capital's streets.

Demonstrators beat drums, pots and pans.

Earlier in the day, demonstrators banged pots and pans and chanted "Same struggle same fight, women's rights are workers rights." Others carried signs saying "Get your rosaries off our ovaries" and "Yes I took a holiday for this, I'm that annoyed" as they marched through the streets of the Irish capital.

People across the country walked out of their offices and joined a day of action dubbed "Strike 4 Repeal," urging the government to hold a constitutional referendum to scrap Ireland's eighth amendment -- a measure that places the right to life of an unborn child on equal footing with the right to life of the mother.

Women and abortion rights activists march in Dublin Wednesday.

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