The UMP party's political leadership held a meeting on Wednesday during which its leader in parliament, Christian Jacob, read out a message from the hackers who posted party leaders' professional and personal phone numbers online, along with addresses and other personal details.
"For all the arrested, the hosing-down of the suburbs, the beaten demonstrators, the spied-upon journalists, the asylum seekers who are ignored or beaten, the stigmatised Roma, for all the UMP's victims... we give you their telephone numbers. An eye for an eye, a tooth for a tooth," the message said.
Several UMP members, including party head Jean-François Copé, on Tuesday said they received numerous calls, mostly insults, on their mobile phones after the numbers were released online.
Copé said he would soon change his number. An aide to Jacob said that several UMP lawmakers were thinking of doing the same.
It is a crime in France to publish a person's phone number without their consent and Jacob said he was lodging a formal complaint with the police for violation of secrecy and theft of electronic data.
"This is extremely serious," Copé said, admitting that he had received "hundreds and hundreds of insulting messages, insults of a very diverse nature."
"We don't know where this comes from," Copé said. "The hacked data is not party data. Is it the (UMP) group at the National Assembly, at the Senate? I don't have any other information."
UMP lawmaker Eric Ciotti said he received several calls on Tuesday night. "Someone called first to tell me that my number was on the internet, a second to tell me that 'he'd had enough of security' and a few anonymous calls," he told AFP.
An AFP correspondent was able easily to find the hacked information online, including the names, job titles, mobile and landline numbers, email addresses, home addresses and roles on committees of more than 600 ranking UMP members.
The data also included officials' ages, how many children they have, what foreign languages they speak and where they went to university.
It was not immediately clear who had hacked the data originally, but posters on French Internet forums noted that if they were ever caught, there would be hell to pay.
Others voiced disappointment that the telephone number of Sarkozy's former supermodel wife Carla was not among the hacked data.