A segment of the Pan-Island Expressway (PIE) in Jalan Anak Bukit will undergo improvements after several vehicles were seen to have skidded out of control along that part of the highway.

The segment, which is near Upper Bukit Timah Road, will see the road and road shoulder re-surfaced, lane markings broadened, the parapet wall re-painted with directional arrows, and new signs installed.

The Land Transport Authority (LTA) said in a Facebook post last Saturday night that these works - an added safety measure after it surveyed the area - will begin this week.

"We have studied this segment of the PIE at Jalan Anak Bukit. The majority of accidents at this location are due to speeding. We also carried out skid resistance readings for this segment and they are within the normal range," the authority said.

The announcement of the works comes after the SG Road Vigilante group uploaded a video on YouTube showing four cars in separate incidents skidding across lanes on the same segment of the PIE.

The LTA, in its Facebook post, provided the link to the 56-second video, which is captioned with the dates Aug 13 to 18.

Aside from speeding, netizens in the comments section have attributed the incidents to balding tyres and oily road surfaces, among other theories.

In its Facebook post, the LTA reminded motorists to exercise greater caution when driving in rainy conditions and to avoid speeding.