Shivraj Patil, the Indian home minister, has resigned over the terror attacks in Mumbai that left around 172 people dead.
Patil submitted his resignation to Manmohan Singh, the Indian prime minister on Sunday. It is not known if Singh has accepted Patil's offer to step down from office.
Shortly afterwards, India's national security adviser, MK Narayanan, also submitted his resignation - which was accepted by the prime minister.
Palaniappan Chidambaram, the Indian finance minister, has been appointed home minister while the prime minister takes on the finance portfolio for an interim period.
A prime ministerial aide told news agency AFP that "more senior members of the government are likely to be shown the door" in the wake of the attacks.
Matt McClure, Al Jazeera's correspondent in Mumbai, said Patil's decision to step down was not a "total surprise" given opposition parliamentarians have repeatedly called for him to resign over the string of attacks in India in the past 12 months.
However, McClure added that while Patil's resignation was in keeping with the concept of ministerial responsibility "the Indian police and intelligence services need to be modernised and better co-ordinated".