SINGAPORE - A network engineer who pushed and fought with a motorcyclist was jailed for a day and fined a total of $3,000 on Wednesday.

Nathan Adrian Tallack, 39, an Australian, admitted to using criminal force on Mr Lee Yao Rong Muhammad Saifuddin Ilyan Lee by pushing him and causing Lee and the machine to fall along Chai Chee Road.

He also pleaded guilty to disturbing the public peace by fighting with the 25-year-old driving instructor. A third charge of causing hurt was considered during his sentencing.

The court heard that Tallack was driving a car along Chai Chee Drive on April 1 this year when he was involved in a near-collision with Mr Lee, who was riding his motorcycle.

Mr Lee thought he saw Tallack give him a rude hand gesture. He was angry and made a U-turn to chase and confront the motorist.

He stopped beside Tallack's car, knocked on the passenger window and motioned for him to lower it.

Both argued, and Tallack exited the car to continue the disagreement. He then pushed Mr Lee. who was seated on his motorcycle, causing rider and machine to topple over.

Two witnesses saw what happened. One of them, property officer Mohamad Sikandar Saraju, 30, recorded the incident with his mobile phone.

Mr Lee stood up and swung at Tallack, who pinned him down on the road. Both fought. Mr Sikandar told them to stop and called the police.

Both men had minor injuries.

Tallack could have been jailed for up to three months and fined up to $1,500 for using criminal force. The maximum penalty for disturbing the public peace is a year's jail and a $5,000 fine.