KUALA LUMPUR: What was initially just a two-inch-thick door became a shock for the owner when the tenant replaced it with a bulletproof-style door, after only two months of renting it.
The 'bulletproof' door is a heavy-duty steel door about seven inches thick, featuring closed-circuit camera surveillance (CCTV) installed at the top.
It resembles a vault, similar to those in banks and includes a 'lookout room' that allows occupants to see outside.
This vault-like security setup was used for illegal bitcoin mining, in which the tenant had also tampered with the electricity meter.
The premises owner, who wishes to be identified as Mohamad Asrul, 47, initially had no suspicions about any unusual activity at his property.
He said the tenant had claimed to be a construction contractor who had recently secured a new contract nearby and requested to rent the shophouse.
"I set the rent at RM1,200 a month for the spacious shophouse, but the tenant asked for a discount, explaining that he hadn't been paid for his construction work yet.
"Eventually, I agreed to reduce the rent to RM850 per month, and he paid for three months in advance," he said.
Asrul, however, began to feel uneasy when he received a call from Tenaga Nasional Berhad (TNB) reporting an issue with the electricity meter and indicating that the electricity consumption was unusually high.
At first, Asrul said he did not suspect anything and attempted to contact the tenant about the electricity usage, but received no response.
"I sent multiple messages to the tenant without getting any reply, before I decided to inspect the shophouse myself.
"Upon arrival, I noticed a steel door at the front, with CCTV cameras mounted above it. The upper window area was obscured by something, making it dark inside.
"Subsequently, I filed two police reports and am now waiting for further investigation from the authorities and TNB," he said.
Make millions of Ringgit montly for free
Illegal bitcoin mining can yield hundreds of thousands to millions of ringgit per month in profits, as the operation avoids electricity costs and generates net gains.
The typical scheme involves renting private or commercial premises for less than three months to conduct illegal bitcoin mining.
This practice results in significant financial damages for the property owner, including high electricity usage costs due to the tenant's activities.
Energy theft related to bitcoin mining has caused an estimated RM3.4 billion in losses over five years, according to data from TNB and the Energy Commission from 2018 to 2023.
Malaysia Cyber Consumer Association (MCCA) president Siraj Jalil said individuals or syndicates engaged in bitcoin mining often steal electricity to maximise their profits.
"Several reported cases involve rented premises, whether residential or commercial, such as shops. The majority of these cases involve commercial properties, as renovations can be disguised, making it difficult to detect illegal activities," he told Harian Metro.
He said these syndicates typically rent a premises for less than three months, after which they leave, taking their bitcoin mining equipment with them.
Siraj noted that these illegal miners often install steel doors and surveillance systems at the premises to protect their high-value equipment.
Property owners usually only become aware of the situation when notified by TNB about unusual electricity consumption or an issue with the electricity meter.