BEIJING: Authorities in China`s restive Xinjiang region believe two suspects, a man and a woman, were behind an explosion that killed seven people and injured 14 others, state media reported Friday.

The pair allegedly tossed explosives from a three-wheeled vehicle into a crowd on Thursday in the suburbs of the city of Aksu, not far from the border with Kyrgyzstan, the Xinhua news agency and Global Times newspaper said.

Five people died at the scene and two others died later in hospital, the report said. The female suspect died in the incident, though it was not immediately clear if she was included in the death toll of seven.

Regional government spokeswoman Hou Hanmin told AFP that the injured male suspect was a member of Xinjiang`s Uighur minority, and that most of the victims were Uighurs as well.

She said investigators had ruled out accident as a cause for the explosion, but said it was too early to say whether the blast was an act of terrorism.

Hou denied reports that martial law had been imposed in Aksu, according to the Global Times.

Aksu is located 650 kilometres (400 miles) southwest of the regional capital Urumqi, which was rocked in July 2009 by violence pitting the mainly Muslim Uighurs against members of China`s dominant Han group.

Nearly 200 people were killed and 1,700 injured in all, the government says, in the worst ethnic violence in China in decades.

China has blamed the unrest on "separatists" but provided no evidence of any organised campaign. More than 25 people have either been executed or received the death penalty for their involvement in the violence, state media say.

BDST: 10:08 HRS, August 20, 2010