Police have noticed that "terrorist attacks" on the mainland are moving south and will make preparations accordingly, the force's commissioner Andy Tsang Wai-hung said yesterday.
But Tsang said there was no particular risk of any such attack at present.
He was responding to Sha Tin district councillors' concerns expressed during a Fight Crime Committee meeting yesterday over a series of attacks in cities across the mainland - the latest at the main railway station in Guangzhou.
Tsang said enforcement officers would take "necessary measures based on information collected". Communities should not be worried and police would alert the public if the risk level was raised, he said.
Tsang also released crime figures for the first two months of the year. A total of 10,820 crimes were reported in the period - about 6 per cent lower than at the same time last year.
Among those arrested were 250 mainland visitors, up about 17 per cent from last year. They were mainly suspected of shoplifting, document forgery and distributing fake yuan notes.
The number of so-called naked chat blackmail cases - in which victims are seduced into disrobing during online video chats then asked for money to avoid the videos being posted online - rose in the first two months of the year. Tsang said the number of such cases had fallen late last year, but there were 85 reports in January and February - a fivefold increase from a year ago.
In a joint operation by officers in Hong Kong, the Philippines, Britain and the United States late last month and early this month, 58 people were arrested in the Philippines for alleged involvement in a global online "sextortion" ring that had snared more than 600 Hongkongers in the past 18 months.
The number of serious drug offences rose 13 per cent to 371, with 470 people arrested. Tsang said teenagers had been hired to help traffic drugs.