The contractor involved in the Indah Water maintenance works at Jalan Universiti Petaling Jaya, where a car had plunged into the open sewage, had been ordered to close the open digging with concrete covers.

The Ministry of Energy, Green Technology and Water, in its media statement, said the initial works had been completed on the same day (yesterday).

"For long-term security control, every open digging will be added with another layer of concrete wall measuring one metre high from the road surface surrounding the open digging.

"This measure aims to prevent any object from falling into the hole from the open digging. At the same time, existing security measures will be streamlined," said the statement.

In the incident at 1.30pm Tuesday, a senior citizen identified as Yong, 86, and his assistant, Marivl Palquing Estoea, 30, survived after the car he was driving skidded before plunging into the 12-metre hole for the sewage project at Section 17 Damansara, near here.

Both victims were sent to the University of Malaya Medical Centre for treatment.