Even Hong Kong's security chief gets scam calls. Imagine going through the business opportunities in your contact list and landing there. Excellent prospecting, everyone. You've reached the person whose brief includes catching you. There is something reassuring about this, briefly. Anyone who has pulled out their phone only to regret answering has company. Then the reassurance wears off. The calls are still getting through.

For the rest of us, an unfamiliar number creates a small nuisance. Answer it, and you might get a scammer. Ignore it, and you might miss a call you wanted. Now you're doing detective work before you've even said hello. The security chief receiving one makes a funny headline because of his job. The tiresome part is familiar to everyone with a phone.

On September 30, we reported a suspected fraud call centre in a Kwun Tong industrial building. An ordinary building, with an operation inside allegedly working through other people's money. That is the less amusing end of this business. Somewhere, a phone rings. Someone answers while getting on with their day.

Police have now arrested six people over a separate alleged investment scam involving agarwood and cryptocurrency. Reported losses reached HK$14 million. The security chief's unwanted call gives us a laugh. People caught in the alleged investment scam have money at stake.