Furious driving, in which drivers cause casualties while trying to escape at high speed - often during illegal racing - is on the rise, says a veteran traffic police officer.
Senior Inspector David Bennett, of the New Territories North police district, said there had been three or four furious driving cases so far this year in the area, compared with just one or two a year previously.
'We are very concerned, as these people have tried every means to escape, including hitting our police cars,' he said.
Police received 240 complaints relating to illegal racing last year, down from 279 in 2010. The force made 2,295 arrests in 332 operations against illegal racing last year, down from 2,951 arrests in 291 operations the previous year.
Bennett said furious driving was unpredictable. A driver might suddenly speed away when police tried to intercept someone for running a red light.
On January 15, a 25-year-old driver led police on a chase of more than 25 kilometres from Pat Heung to Mong Kok. An officer was injured when he tried to intercept the car.
Bennett said pursing cars was dangerous and police made personal safety a priority. They would not make an unnecessary chase. 'At the end of the day, if we have the car plate number we can follow up the case,' he said.
One of the ways police combat illegal car racing and furious driving is to use unmarked cars fitted with advanced equipment to gather evidence. These cars can detect a vehicle's speed several hundred metres away and can be driven as fast as 260km/h to chase suspect vehicles.
Bennett said there were four unmarked cars in his region and a fifth would be bought soon.
Car racing generally happened at night and involved up to four cars on highways such as the Tolo Highway and Tuen Mun Road. The drivers were usually men aged 20 to 40.
Bennett said they usually race from a remote site to an urban area, such as from Lok Ma Chau to Mong Kok, a race that takes 15 minutes.
Cars modified for racing were seldom seen now, as these days production models came with high-powered engines allowing for high speeds. Porsches and Ferraris were among the cars used in races.
Superintendent Shylock Wong Yiu-ming, responsible for law revision and projects at the police traffic headquarters, said car racing was seldom premeditated, making it difficult for officers to collect evidence.