As many as 21 persons were killed and 8 others critically injured in a massive explosion at a firecracker factory in Kakinada district on Saturday.Andhra Pradesh Chief Minister N Chandrababu Naidu announced an ex-gratia of Rs 20 lakh for the kin of deceased in the blast. He assured that the medical expenses for the injured will be taken care of by the government. He also ordered the suspension of four senior officials of Kakinada district for dereliction of duty. The CM said an inquiry would be conducted into the incident.Prime Minister Narendra Modi said he was pained by the tragic incident. In a post on ‘X’, he announced Rs 2 lakh ex gratia from the PMNRF to the next of kin of each deceased and Rs 50,000 for the injured persons.Andhra Pradesh Minister Kandula Durgesh said: “This is the biggest blast in the state. Officials are inquiring into the cause of the fire, which led to the blast.”