Metal sheet worker who made airguns and fired at neighbouring flats jailed, fined

Wan Ting Koh
·4 min read
The Singapore State Courts. (PHOTO: Dhany Osman / Yahoo News Singapore)
The Singapore State Courts. (PHOTO: Dhany Osman / Yahoo News Singapore)

SINGAPORE — Captivated by the firing mechanism of a Nerf gun, a metal sheet worker decided to make his own airgun using discarded scrap material from his workplace and following video tutorials.

Lee Keng Hee, a 64-year-old Singaporean, manufactured three airguns and tested them out by shooting metal ball bearings at a cardboard box in his living room. When that proved successful, he used trees for target practice and then turned to shooting at residential blocks from his living room and kitchen windows.

Lee was jailed for 18 weeks and fined $2,000 on Wednesday (16 December) after he pleaded guilty to one charge of committing a rash act which endangered the safety of others, and one charge of manufacturing an arm without authorisation – a breach of the Arms and Explosives Act.

Curiosity about firing mechanism of Nerf gun led to construction

Lee was employed as a sheet-metal worker at Actinium Engineering at the time of the offence.

Around 2017, he came across a Nerf toy gun and became curious about its firing mechanism. Upon studying it, he realise that the toy made use of compressed air to propel “Nerf” foam bullets.

He attempted to recreate this mechanism by making his own PVC airgun, but failed. He then decided to make a more powerful airgun from scratch using metal, and began studying airgun-making tutorials on YouTube.

Later that year, Lee set about constructing his first airgun. Due to difficulties in construction, he began a second airgun using a different design. He bought 100 6mm steel ball bearings and 100 8mm steel ball bearings to use as bullets.

He then used the 6mm ball bearings to test the two airguns in his home using the cardboard box. While the first airgun shot at a range of about 1 metre, he considered it a failure. The second airgun, however, easily penetrated the cardboard box.

Curious about the second airgun’s full firing range, he began shooting at trees – planted about 10 to 15 metres from his Jurong West HDB block – from his living room’s window. He checked for impact by listening for sounds or observing whether the leaves moved.

As the second airgun was spoilt after several uses, Lee made a third airgun with a new and improved design. He intended for it to be more powerful than his first two prototypes. The work spanned three months and was completed in October 2018.

Upon completion, Lee again tested out the airgun on the same targets but graduated to using nearby HDB blocks as target practice. He shot at trees about 10 times and at the HDB blocks four to five times on his first day using the airgun.

He continued using a block as target practice until April last year, shooting no fewer than 200 6mm ball bearings with the three airguns.

One resident at the target block lodged a police report on 3 April last year, bringing Lee’s target practice to an end.

Damages to residents’ windows

Police conducted door-to-door enquiries around the victim’s block, discovered Lee in possession of the homemade weapon and arrested him. After news of his arrest, seven other residents lodged police reports stating their windows had suffered damage. Another had reported the damage to the police earlier on 1 January 2019.

Tests conducted on the airgun determined the speed of the ball bearings to be 80 to 130 metres per second upon impact, capable of causing pain and non-lethal injuries.

Deputy Public Prosecutor Regina Lim sought four months and six weeks’ jail and a fine for Lee.

Lee’s lawyer Favian Kang told the court that his client had voluntarily made restitution by selling off jewellery left behind by his late mother to raise funds.

Kang added that his client last worked as a factory cleaner to support his wife and son. He also gave full cooperation to the authorities, assisting them with sketches and inquiries, which was a strong indication of remorse.

Kang sought a short jail term and a small fine for Lee.

For manufacturing an arm without license, Lee could have been jailed three years or fined up to $10,000. For committing a rash act to endanger safety, he could have been jailed up to six months, and/or fined up to $2,500.

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