Police and ambulances were seen rushing in, according to another broadcaster, the privately owned Dogan news agency.
The station also serves as a police barracks, TRT said, citing a statement from the local governor. It was not immediately clear how many police and civilians were among the dead and wounded.
Prime Minister Binali Yildirim said on live television there had been an attack on a police station in Van but did not elaborate.
No one immediately claimed responsibility for the attack. Kurdish militants frequently target police stations and other security force outposts with car bombs.
Turkey's mainly Kurdish southeast has been scorched by violence since a 2-1/2-year ceasefire between the state and the outlawed Kurdistan Workers Party fell apart in July last year.