Hunt for gunman after 39 shot dead in Istanbul nightclub
Armed attacker opened fire at a popular nightclub Reina, with up to 600 people inside.
Turkish media are reporting two attackers were involved in an attack at a nightclub in Istanbul.
NTV Television, a state run news agency, said the attack occurred at the Reina nightclub in the city.
It is believed one attacker is still inside the club, according to CNN Turkey.
Ambulances and police vehicles have been seen outside the club in the Ortakoy district.