At least four people were killed and more than 20 injured when a bus collided head-on with a truck in West Midnapore district of West Bengal on Wednesday morning, police said.The accident took place around 7:10am Chandrakona area, about 132km west of state capital Kolkata. “Four persons died and more than 26 were injured in the accident. The condition of some of the injured is critical,” West Midnapore’s superintendent of police Alok Rajoria said.The driver of the bus, travelling from Kharagpur towards Tarakeshwar, swerved to avoid hitting a rickshaw and collided with a truck coming from the opposite direction. Locals said there was fog in the area when the accident happened.The drivers of both vehicles died in the mishap. The injured were initially taken to Chandrakona Hospital from where 15 people were referred to Midnapore Medical College and Hospital.Road accidents have become a headache for the state government with chief minister Mamata Banerjee encouraging a campaign with the slogan ‘Safe Drive, Save Life’.While Banerjee has been regularly urging drivers to adopt safe practices on the road, police in the state have taken novel measures of stopping vehicles on highways and offering drivers water to splash on their face and hot tea to sip to fight sleep.