Twenty people were injured, one critically, in accidents involving minibuses in the Cross-Harbour Tunnel and Lion Rock Tunnel before dawn yesterday.
A Sha Tin-bound car swerved into the opposite lane at 4.30am in Lion Rock Tunnel and crashed into a minibus. The car then collided with a second minibus.
Two men in one of the minibuses and two women in the car were treated at Queen Elizabeth Hospital.
Both minibus drivers, aged 27 and 42, were unhurt.
The driver of the car was also uninjured. He was arrested for refusing to take a breathalyser test and was being held last night for questioning. No one has been charged.
The Kowloon West traffic unit is investigating the crash.
An hour earlier, a Kwun Tong-bound minibus and a car collided head-on in the Cross-Harbour Tunnel about 200 metres from the Hung Hom exit.
The front of the car was crushed and its male driver, 22, was trapped. He had lost consciousness by the time firefighters freed him about 30 minutes later.
The minibus driver, 63, and his 14 passengers were also injured. They were bandaged by paramedics at the scene. Some were able to walk out of the tunnel and get into ambulances.
All the injured were taken to Queen Elizabeth and Ruttonjee hospitals. A 25-year-old woman was later transferred to Eastern Hospital.
The driver of the car was in a critical condition and the minibus driver was in a serious condition. The others were discharged after treatment.
Police said both drivers were unable to take a breathalyser test because of their injuries.
The Hong Kong Island traffic unit is investigating whether the car or the minibus crossed the opposite lane in the incident.
Police said there was two-way traffic in both of the tunnels.
Figures from the Transport Department show 441 minibuses were involved in accidents in the first five months of the year.