Maharashtra Chief Minister Sushilkumar Shinde has called a high-level meeting to discuss the situation following the Ghatkopar bomb blasts, which killed four persons and injured 31 on Monday night.
Deputy Chief Minister Chhagan Bhujbal, Home Secretary U K Upadhyaya, Chief Secretary Ajit Nimbalkar, Director General of Police O P Bali and Commissioner R S Sharma are expected to attend the meeting on Tuesday morning.
Measures to tackle terrorist threats will be discussed.
According to official sources, two bombs were planted in the bus that exploded on Monday.
A red alert has been sounded all over Maharashtra and combing operations have been launched to trace those behind the blasts.
Just seven months back a blast in a BEST bus in Ghatkopar had left two dead and several injured.
Five explosions have occurred in the last eight months, killing 15 people and injuring more than 100.