A Lebanese judge began questioning the country's security chiefs about the explosion in Beirut, AP reported.
The cabinet was due to meet later Monday amid rumors that the government might resign en masse.
If four more ministers resign, the cabinet will collapse, gaining interim status until a new government is formed.
The Beirut blast on August 4 is believed to have been caused by a fire that exploded 2,750 tons of ammonium nitrate. The material has been stored in the port since 2013, despite numerous hazard warnings.
The blast killed at least 200 people, injured about 6,000, destroyed the country's main port, and damaged much of the capital. The damage from the blast is estimated at between $10 and 15 billion, almost 300,000 people were left homeless