The attack on the police station in Istanbul's Sultanbeyli neighborhood on Monday caused part of the three-story building to collapse, according to Turkey's state-run Anadolu Agency.
Nearby buildings and parked cars were also damaged in the explosion, the private Dogan news agency reported.
Ten people were reported to have been injured, including seven police officers.
Police reports said the assailants detonated a car bomb near the station. Earlier reports spoke of a suspected suicide attack.
Turkish media say unknown attackers later shot at police while they were inspecting the site of the explosion, with a policeman and two assailants being killed in an ensuing gunfight.
There was no immediate claim of responsibility for the attack, but it comes as Turkey is involved in military action both against "Islamic State" ("IS") militants in Syria and rebels of the Kurdistan Workers' Party or PKK, mostly in northern Iraq.
The PKK, which has been waging a three-decades-long insurgency against Ankara for more rights for the country's Kurdish minority, has been blamed for a number of attacks in the past weeks amid a renewed surge of violence.
Turkey launched aerial attacks on "IS" positions in Syria last month following a suicide bombing in Turkey blamed on the jihadist group and an incident in which "IS" fighters fired at Turkish soldiers from across the boder in Syria, killing one soldier.
US Consulate attack
In a separate incident early on Monday morning, two gunmen opened fire on the US Consulate building in the city, according to Turkish media reports.
The attackers succeeded in escaping after a brief gunfight with police, according to the Dogan news agency.
Turkish news agencies said police later captured one person in connection with the attack. The Dogan news agency said it was a woman who had been injured in the gunfight and hid in a nearby building.
No one else was harmed in the attack.
tj/kms (AP, dpa)