BANGKOK, June 8 -- Four people, including two tourists from China's Hong Kong and two Thais, were killed in a van crash in central Thailand, the Chinese embassy said on Monday.

The van was carrying seven people, including the driver, when it crashed into a tree at about 5 p.m. local time Sunday (1000 GMT) on an expressway in the central Phetchaburi province, the embassy said, citing the Thai police.

Three other Hong Kongers were injured, including a four-year- old boy, the embassy said, adding the injured have been sent to the hospital.

A female and a male tourist from Hong Kong, as well as the Thai driver, were among those killed, with the cause of the accident under investigation, according to the embassy.

Officials from the Hong Kong Special Administrative Region were arriving to handle the incident, and the embassy would provide assistance, it said.