(Reuters) - A group of Indians including journalists and lawyers whose phones were hacked via Facebook's (FB.O) WhatsApp messaging platform asked the government on Friday to make public its ties with the Israeli firm accused of deploying the spyware. WhatsApp last week sued Israel's NSO Group, accusing it of helping clients break into the phones of roughly 1,400 users - including diplomats, political dissidents, journalists, military and government officials - across four continents. "It is a matter of public concern whether Indian tax payer money has been spent on this kind of cyber surveillance...," the Indian group, comprising journalists, lawyers, academics, writers and social activists, said in the letter. The group of Indian users said that the spyware had compromised not just their safety but also the security of their friends, family, clients and sources. "We seek an answer from the Government of India about whether it was aware of any contract between any of its various ministries, departments, agencies, or any State Government, and the NSO Group or any of its contractors to deploy Pegasus or related malware for any operations within India?"