SINGAPORE - About 100 people were evacuated and one person was injured when an explosion blew open a section of the building at the Audi service centre in Ubi on Tuesday morning.

The Singapore Civil Defence Force (SCDF), in a Facebook post, said preliminary investigations found that a fire had broken out in the motor room located on the ground floor of the building. However, it burned out before SCDF officers arrived.

The cause of the fire is under investigation.

SCDF said its officers arrived to find that a section on the side of the building had collapsed.

The explosion happened at about 8.55am in the building, located at 55 Ubi Road 1, SCDF said.

Several members of the public had seen smoke coming from the motor room and used fire extinguishers to put the fire out before SCDF officers arrived.

However, one of them fell and got abrasions on both hands. He was taken to Raffles Hospital, SCDF said.

When The Straits Times arrived, officers from the SCDF were seen examining the rubble-strewn site.

People working in the area said they heard a loud explosion in the morning and experienced aftershocks in its wake.

Mr Kumar P. Rajagopal, a facilities manager at Crocodile House located in the building next to the service centre, said he heard a big explosion when he was in his seventh-storey office.

The 57-year-old manager said: “The explosion shook the whole building and the stacked boxes in the office fell over.

“I went outside and saw the wall collapsed with glass shards scattered all around. There was smoke coming from one of the tanks. Even my friend in the neighbouring Yi Guang building said he felt the building shake.”

Audi, in a Facebook post on Tuesday, said the Ubi 55 building will be closed temporarily while investigations continue. It added that Audi Singapore is working with the authorities to identify the cause of the explosion.

In response to queries, Audi said SCDF has certified that the Ubi 55 building is safe to occupy. It added that the Audi service centre at 55 Ubi Road 1 will remain closed for now, but hopes to resume operations by the end of the week.

Meanwhile, customers with cars at the service centre or upcoming appointments in the next few days have been contacted and alternative arrangements have been made. There will be no new appointments accepted until the service centre reopens.

The Building and Construction Authority (BCA) said it has issued a closure order for the affected section of the building, which has been cordoned off for the safety of the public.

A BCA spokesman said: “BCA’s engineers have inspected the building and found localised damage to non-structural elements in the motor room, including brick walls, false ceilings and lift doors. The rest of the building is not affected by the explosion and is safe.”

A professional engineer appointed by the building owner will be required to conduct a detailed investigation and recommend permanent rectification works to be carried out, the spokesman added.

• Additional reporting by Judd Siow