A female suicide bomber has blown herself up in Istanbul, injuring two policemen, authorities said.

The woman entered a police station and reported a missing wallet before detonating a bomb, Istanbul governor Vasip Sahin said.

The attack occurred in the Sultan Ahmet district, a popular tourist destination.

It is the second attack on police in a week in Istanbul. On Thursday, police subdued a man after he threw grenades and fired a weapon at officers near the offices of the prime minister.

The leftist Revolutionary People's Liberation Party-Front, or DHKP-C, said it carried out the Thursday attack.

Mr Sahin said that police are still trying to identify the woman who died in Tuesday's attack.

"She spoke in English, entered (the police station) on the pretext that she had lost her wallet," he said.