A seven-month-old baby has died after a crash on the A1 as officers investigate whether the incident was linked to icy conditions.
Lincolnshire Police were called to the southbound carriageway at 22:50 GMT on Thursday, near the A52 junction at Grantham after a yellow Honda Jazz left the road and crashed into a tree.
The baby boy suffered serious injuries and was taken to hospital but died just after 05:00 on Friday. A woman travelling in the car also suffered serious injuries.
The southbound carriageway remains closed while investigations take place.
Lincolnshire Police said two other people were in the vehicle and were not seriously hurt.
The force said it was keeping an "open mind" over the cause of the collision but said it could be linked to icy conditions in the area.
The family of the boy is being supported by specially-trained officers.
Lincolnshire Police said it was keen to speak to anyone who may have been driving in the area at the time of the incident or over the past few days.
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