SINGAPORE - A man is accused of beating up an SBS Transit bus driver after he boarded the bus without wearing a mask.

Ja'afally Abdul Rahim was charged on Thursday (Sept 17) with one count of voluntarily causing hurt to bus driver Low Kok Weng by pushing him in the face along Pasir Ris Drive 1 at about 2.50pm on Tuesday.

The 52-year-old also faces one charge of possessing a knife with a 6cm-long blade, which is an offensive weapon under the law, at that time.

In an Facebook post on Wednesday, SBS Transit said a 52-year-old commuter had boarded service 21 along Pasir Ris Drive 6 at about 2.45pm the previous day. He was not wearing a mask at that time, and only put it on later.

The man began hurling vulgarities at the bus driver, who was not named in the Facebook post, and continued to do so for the duration of two bus stops.

After the driver stopped the bus in front of Block 210 along Pasir Ris Drive 1 to wait for the police to arrive, the commuter started physically abusing him.

"The man grabbed the bus captain's neck and collar, holding on for more than a minute. He refused to let go even when our bus captain pleaded with him to do so," said SBS Transit.

"Our bus captain could be seen cowering with his arms shielding his face as the man started punching him repeatedly on the head," the public transport operator added.

It was not clear what had sparked the attack.

Three men at the bus stop boarded the bus and tackled the man, dragging him out of the bus. They then pinned him down until the police arrived.

SBS Transit said the bus driver was taken conscious to Changi General Hospital after the assault and given three days of medical leave.

Attaching a photo of the battered driver in the post, the public transport operator said: "We are thankful that he did not sustain any serious injuries. He is shaken but remains in good spirits."

Ja'afally has been granted bail of $15,000 and is expected to be back in court on Oct 8.

If found guilty of voluntarily causing hurt, Ja'affally can be jailed for up to three years and/or fined up to $5,000.

He can also be jailed up to three years and punished with not less than six strokes of the cane if convicted of possessing an offensive weapon.