SINGAPORE - A plumber was fined $4,500 on Thursday (Dec 14) for setting off a flare, resulting in a huge commotion.

Aw Chong Loong, 50, pleaded guilty to committing an act so negligent as to be likely to cause hurt or injury. The incident happened at Block 226C, Ang Mo Kio Avenue 1, on Sept 26.

He failed to ascertain the nature of the parachute signal flare, an explosive substance commonly used in marine distress situations, and set it off while it was pointed in the direction of a hawker centre.

Deputy Public Prosecutor Yang Ziliang said stallholder Tan Yong Joo was seated in front of his stall at the hawker centre at about 4.30pm that day when he heard a loud boom.

He turned to his stall and saw a "huge ball of fire about the height of (his) knee", with some sparks and smoke.

The fire was put out by a passer-by. No one was hurt.

During a 30-hour operation, police scoured 23 blocks nearby to find out the cause of the fire.

When the police asked him, Aw, who operates from his family's shop in the block, initially claimed that he had not seen anything.

But closed circuit television footage and extensive ground inquiries identified him as a possible suspect. Aw came clean the next day.

DPP Yang said Aw had been collecting discarded items for the past 30 years. He was clearing the store at the back of his family's medical hall that afternoon to make way for a new tenant when he saw a cylindrical object, covered with dust, on a shelf.

He took it outside to have a closer look. He did not read what was written on it.

After he opened the red cap, a grey disc dropped out and he threw it into a nearby dustbin. He then opened the other cap and saw a rectangular button and a pin on its side. The pin was attached to a short nylon string.

Curious, he pressed the button but nothing happened. Pointing the object towards the hawker centre, Aw pulled the string and pin while pressing the button. Immediately, there was a lot of smoke and a whizzing sound. There was no fire. He was alarmed and immediately went back into the shop.

Subsequently, he realised that the commotion outside and the incident at the hawker centre may have been due to the object he had activated.

The court heard that he did not admit to his role initially as he did not want people to see him being arrested, or be known as the one who had set the object off, resulting in a commotion.

Aw could have been jailed for up to one year and/or fined up to $5,000.