The US Capitol police chief has told waiting reporters that they believed there was a child in the car involved in the incident and that he did not have any information on the person driving the car.
He said that multiple scene involved are now secure and said he had no information that the incident was related to terrorism and is anything other than an isolated incident.
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Three deadly attacks, including a twin explosion in a crowded market place, across Pakistan have left dozens dead and many injured.
Expect cloudy conditions with some light rain on Saturday morning before brighter spells develop later in the southeast.
More than 140 people are missing and feared to have been buried under debris following a landslide in China.