TWO serious accidents took place in the past four days.

A motorcyclist suffered serious head injuries after his machine went over a 2m-long wooden plank early Friday morning along the Pan-Island Expressway towards the airport.

The 26-year-old man lost control of his motorcycle at about 12.15am and skidded. He was semi-conscious when he was taken to the Changi General Hospital.

In another incident on Tuesday, a cyclist sustained serious head injuries after a taxi collided into the rear of his bicycle along Victoria Street towards Kallang Road.

The 68-year-old man was conscious when he was rushed to Tan Tock Seng Hospital but his condition turned critical and he lapsed into a coma.