(CNN) Hong Kong protesters are appealing for foreign support in their fight for political freedom, calling on world leaders to act ahead of the summit of the Group of 20 major economies in Osaka, Japan, this week.

Hundreds of demonstrators rallied in the city center and marched to consulates of G20 nations, including the United States, the United Kingdom and Japan, to deliver letters urging leaders to back their bid for the full withdrawal of a controversial extradition bill.

Carrying signs reading "Liberate Hong Kong," activists at an evening assembly, many of them wearing black, sang protest anthems and called on G20 leaders to defend their rights. The demonstrators hope their efforts will get the bill onto the G20 agenda, despite a top Chinese foreign ministry official saying that Beijing would not allow it

Protesters rally against the extradition bill ahead of the G20 summit.

Hundreds of thousands of people have taken to the streets in Hong Kong over the past two weeks to protest a government extradition bill, which many fear could be used to deport political activists and dissidents to mainland China.

Although city leader Carrie Lam announced over a week ago that the government would suspend the bill, opponents want to see it scrapped entirely. They are also calling for the police to be investigated for alleged brutality after officers fired rubber bullets and tear gas this month at a crowd that had surrounded the government headquarters.

Protesters outside the US Consulate petition for support.

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