A 76-year-old man whose car hit another vehicle resulting in a Suffolk teacher being air-lifted to hospital with life-threatening injuries told police he thought a medical problem had caused him to lose consciousness immediately before the collision, a court has heard.

John King told officers that he could remember coming on to a slip road off the A14 at Tot Hill near Stowmarket and then feeling “like a light had been switched off”.

He denied feeling as if he was going to sleep and said he would have stopped the car if his eyes had been getting heavy or closing.

“I felt drowsy but I wasn’t dropping asleep,” he told police.

King, now 78, of Witney Close, Ipswich, has denied causing serious injury by dangerous driving on April 2 last year.

The court heard that after he was charged with the offence King replied: “I think it’s a medical problem that caused a loss of consciousness.”

Helen Hemy, a teacher at Bacton Middle School, and her husband David were driving home after playing tennis in Stowmarket when their black Alfa Romeo was hit by a Lexus driven by King.

As a result of the collision, which happened on a roundabout at the top of a slip road off the A14 at Tot Hill, Mrs Hemy spent 15 days in Addenbrooke’s Hospital, Cambridge, during which time she was placed in an induced coma on two occasions.

All the ribs on the left side of her body were broken as well as two on the right side and she also suffered a blood clot on her brain, a punctured lung, internal bleeding and had her spleen removed.

Following the collision, which happened shortly before 4.30pm, King told police he had started to feel “drowsy” near Woolpit and had taken a slip road off the A14 at Tot Hill with the intention of stopping at a petrol station for a sleep or to get a can of drink.

He had no recollection of the collision and told police it felt as if “someone had switched him off.”

“The prosecution case is that the defendant had sufficient warning of feeling drowsy but continued to drive and in doing so drove dangerously with significant consequences to Mrs Hemy,” said Christopher Paxton, prosecuting.

He said that from Woolpit to Tot Hill there were four lay-bys where King could have stopped to “get himself together”.

The trial continues today.