At least 21 people have burned to death after a bus fell into a ditch and caught fire in central India, police say.

Constable Vikram Singh, at the police control room in Panna district, said the death toll from Monday's crash may rise as police teams cut into the wreckage of the charred bus.

Panna district is in the state of Madhya Pradesh. 

Singh said another 14 people had been injured, adding that it was not clear how many passengers were travelling on the private bus.

He said the cause of the accident was also being investigated.

Road accidents are common in India due to rash driving and poor conditions of roads and vehicles.

Elsewhere in India, in Sangli district, nine people have been killed and five others were injured in Monday evening's fireworks factory blast.

It is still not clear how the fire had started. Accidental explosions are common at Indian fireworks factories.

In 2012, 34 people were killed and 30 others were injured as a massive blaze at a fireworks factory in the southern Tamil Nadu state.

Source: Agencies