At least seven people were killed and several others injured as militants attacked a police station in Karachi on Friday morning.

Some eight to 10 militants breached the 5-story Karachi police at 7:10 pm on Friday, according to reports.

Police snipers took up positions near the station and all lights in the area were switched off. Three of the assailants were killed in the attack.

"I can so far confirm that the KPO building has been cleared. 3 terrorists have been neutralized," Sindh government spokesperson Murtaza Wahab tweeted.

The Pakistani Taliban, or Tehreek-e-Taliban Pakistan (TTP), took responsibility for the attack in a message sent by their spokesman to journalists.

"Can't exactly tell how many terrorists have entered but there are at least more than five," Deputy Inspector General Irfan Baloch told Reuters.

The station houses offices of the city's most senior police. Baloch said there could have been up to 30 police at the station at the time of the attack.

The Islamist TTP, separate from the Taliban ruling neighboring Afghanistan, has recently increased attacks on police in the northwest of Pakistan as part of its campaign against the government in Islamabad.