Kuala Lumpur City Hall (DBKL) project implementation and maintenance deputy director-general Datuk Mohd Najib Mohd told reporters at the scene of the incident that the repair work is being carried out.
In the 9.30am incident on 2 July, a section of the 35m tunnel under construction to build a four-lane underpass collapsed, causing a 5m deep sinkhole.
Azizan Ismail, Kuala Lumpur Fire and Rescue Department assistant director (operations), said there were two soil movements detected in the area at 9.30am and 12.20pm.
"We fear there may be more cave-ins along the tunnel," he said.
Azizan said a Syarikat Bekalan Air Selangor (Syabas) pipe broke during the cave-in, and Syabas has been requested to seal the pipe to avoid worsening the situation.
"As a temporary safety measure, the contractor is now pumping water out from the site before piling work can be carried out to strengthen the area," he said.
Azizan said the Department is still waiting for investigation by Syarikat Prasarana Negara, the KL Monorail operator, to ensure the monorail pillars at the location were not affected.
Meanwhile, Mass Rapid Transit Corp. Sdn Bhd (MRT Corp.) has denied that the road collapse at the Jalan Pudu-Jalan Imbi-Jalan Hang Tuan intersection on 2 July was connected with the MRT project.
"MRT Corp wishes to state unequivocally the alignment of the MRT Sungai Buloh-Kajang Line does not pass that location," they said in a statement.
MRT Corp. advised motorists to heed all traffic signage implemented by the Dewan Bandaraya Kuala Lumpur (DBKL) and the police.
Kuala Lumpur Fire and Rescue Department said that the tunnel, which is part of Pudu underpass project by Kuala Lumpur City Hall (DBKL), sunk twice. It said two excavators were in the tunnel when the incident happened, but no casualties were reported.