The government’s cybersecurity agency Indian Computer Emergency Response Team (CERT-In) on Thursday said it has started its investigation into the issue of Apple threat notification received by several opposition Members of Parliament (MPs), and a notice has been sent to the company.

“CERT-In has started its probe...they (Apple) will cooperate in this probe,” S Krishnan, Secretary, Ministry of Electronics and IT, said on Thursday.

Speaking on the sidelines of an event here, he confirmed that the notice has been sent to Apple. When asked Apple for comments, the company said it did not have an immediate comment to make.

Earlier this week, the iPhone-maker had reacted to the claims of Opposition leaders, saying it is possible that some threat notifications may be false alarms and some attacks may not be detected. However, it refused to say what triggered warnings received by Opposition leaders.

“Apple does not attribute the threat notifications to any specific state-sponsored attacker,” it said in a statement on Tuesday adding that state-sponsored attackers are “very well-funded and sophisticated, and their attacks evolve over time”.

“Detecting such attacks relies on threat intelligence signals that are often imperfect and incomplete. It’s possible that some Apple threat notifications may be false alarms, or that some attacks are not detected,” Apple had said.

The development came after Rajeev Chandrasekhar, Minister of State for Electronics and IT had earlier this week, said that the government wants Apple to clarify if its devices are secure and why ‘threat notifications’ were sent to people in over 150 countries, given the company’s repeated claims about its products being designed for privacy.

Several Opposition leaders on Tuesday claimed they have received an alert from Apple warning them of “State-sponsored attackers trying to remotely compromise” their iPhones and alleged hacking by the government.

Congress Chief Mallikarjun Kharge, party leaders Shashi Tharoor, Pawan Khera, KC Venugopal, Supriya Shrinate, T S Singhdeo and Bhupinder S Hooda; Trinamool Congress MP Mahua Moitra, CPI(M) General Secretary Sitaram Yechury and SP chief Akhilesh Yadav received the alert.

Ashwini Vaishnaw, Minister of Communications and IT, also has categorically rejected the opposition’s attack on the government, saying “compulsive critics” were indulging in the politics of “distraction”, as they could not tolerate the country’s progress under the PM’s Narendra Modi leadership.

“The government of Bharat takes its role of protecting the privacy and security of all citizens very seriously and will investigate to get to the bottom of these notifications...In light of such information and widespread speculation, we have also asked Apple to join the investigation with real, accurate information on the alleged state-sponsored attacks,” Vaishnaw had said.