Internet freedom activists in Poland are set to hold more demonstrations later today.
They are angry about their government signing an international treaty to enforce intellectual property rights on the web.
Similar protests were held yesterday following the decision by ministers to back the Anti-Counterfeiting Trade Agreement.
Poland’s signing of the treaty, known as ACTA, still needs parliamentary approval.
Prime Minister Donald Tusk said: “I don’t think that these international treaties can be greeted with delight by those who have become used to certain internet practices, which aren’t legal under Polish law.”
Activist group Anonymous responded to the move by hacking Polish government websites.
It says the treaty amounts to censorship.
ACTA also needs the approval of the European Parliament and all EU member states before it can come into force across the 27-member bloc.